* and join trees.
*
*
- * Portions Copyright (c) 1996-2005, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2015, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/nodes/primnodes.h,v 1.109 2005/10/15 02:49:45 momjian Exp $
+ * src/include/nodes/primnodes.h
*
*-------------------------------------------------------------------------
*/
#include "access/attnum.h"
#include "nodes/pg_list.h"
-#include "nodes/value.h"
/* ----------------------------------------------------------------
*
* Note: colnames is a list of Value nodes (always strings). In Alias structs
* associated with RTEs, there may be entries corresponding to dropped
- * columns; these are normally empty strings (""). See parsenodes.h for info.
+ * columns; these are normally empty strings (""). See parsenodes.h for info.
*/
typedef struct Alias
{
INH_DEFAULT /* Use current SQL_inheritance option */
} InhOption;
+/* What to do at commit time for temporary relations */
+typedef enum OnCommitAction
+{
+ ONCOMMIT_NOOP, /* No ON COMMIT clause (do nothing) */
+ ONCOMMIT_PRESERVE_ROWS, /* ON COMMIT PRESERVE ROWS (do nothing) */
+ ONCOMMIT_DELETE_ROWS, /* ON COMMIT DELETE ROWS */
+ ONCOMMIT_DROP /* ON COMMIT DROP */
+} OnCommitAction;
+
/*
* RangeVar - range variable, used in FROM clauses
*
char *relname; /* the relation/sequence name */
InhOption inhOpt; /* expand rel by inheritance? recursively act
* on children? */
- bool istemp; /* is this a temp relation/sequence? */
+ char relpersistence; /* see RELPERSISTENCE_* in pg_class.h */
Alias *alias; /* table alias & optional column aliases */
+ int location; /* token location, or -1 if unknown */
} RangeVar;
+/*
+ * IntoClause - target information for SELECT INTO, CREATE TABLE AS, and
+ * CREATE MATERIALIZED VIEW
+ *
+ * For CREATE MATERIALIZED VIEW, viewQuery is the parsed-but-not-rewritten
+ * SELECT Query for the view; otherwise it's NULL. (Although it's actually
+ * Query*, we declare it as Node* to avoid a forward reference.)
+ */
+typedef struct IntoClause
+{
+ NodeTag type;
+
+ RangeVar *rel; /* target relation name */
+ List *colNames; /* column names to assign, or NIL */
+ List *options; /* options from WITH clause */
+ OnCommitAction onCommit; /* what do we do at COMMIT? */
+ char *tableSpaceName; /* table space to use, or NULL */
+ Node *viewQuery; /* materialized view's SELECT query */
+ bool skipData; /* true for WITH NO DATA */
+} IntoClause;
+
/* ----------------------------------------------------------------
* node types for executable expressions
* Note: during parsing/planning, varnoold/varoattno are always just copies
* of varno/varattno. At the tail end of planning, Var nodes appearing in
* upper-level plan nodes are reassigned to point to the outputs of their
- * subplans; for example, in a join node varno becomes INNER or OUTER and
- * varattno becomes the index of the proper element of that subplan's target
- * list. But varnoold/varoattno continue to hold the original values.
- * The code doesn't really need varnoold/varoattno, but they are very useful
- * for debugging and interpreting completed plans, so we keep them around.
+ * subplans; for example, in a join node varno becomes INNER_VAR or OUTER_VAR
+ * and varattno becomes the index of the proper element of that subplan's
+ * target list. Similarly, INDEX_VAR is used to identify Vars that reference
+ * an index column rather than a heap column. (In ForeignScan and CustomScan
+ * plan nodes, INDEX_VAR is abused to signify references to columns of a
+ * custom scan tuple type.) In all these cases, varnoold/varoattno hold the
+ * original values. The code doesn't really need varnoold/varoattno, but they
+ * are very useful for debugging and interpreting completed plans, so we keep
+ * them around.
*/
-#define INNER 65000
-#define OUTER 65001
+#define INNER_VAR 65000 /* reference to inner subplan */
+#define OUTER_VAR 65001 /* reference to outer subplan */
+#define INDEX_VAR 65002 /* reference to index column */
+#define IS_SPECIAL_VARNO(varno) ((varno) >= INNER_VAR)
+
+/* Symbols for the indexes of the special RTE entries in rules */
#define PRS2_OLD_VARNO 1
#define PRS2_NEW_VARNO 2
{
Expr xpr;
Index varno; /* index of this var's relation in the range
- * table (could also be INNER or OUTER) */
+ * table, or INNER_VAR/OUTER_VAR/INDEX_VAR */
AttrNumber varattno; /* attribute number of this var, or zero for
* all */
- Oid vartype; /* pg_type tuple OID for the type of this var */
+ Oid vartype; /* pg_type OID for the type of this var */
int32 vartypmod; /* pg_attribute typmod value */
- Index varlevelsup;
-
- /*
- * for subquery variables referencing outer relations; 0 in a normal var,
- * >0 means N levels up
- */
+ Oid varcollid; /* OID of collation, or InvalidOid if none */
+ Index varlevelsup; /* for subquery variables referencing outer
+ * relations; 0 in a normal var, >0 means N
+ * levels up */
Index varnoold; /* original value of varno, for debugging */
AttrNumber varoattno; /* original value of varattno */
+ int location; /* token location, or -1 if unknown */
} Var;
/*
typedef struct Const
{
Expr xpr;
- Oid consttype; /* PG_TYPE OID of the constant's datatype */
+ Oid consttype; /* pg_type OID of the constant's datatype */
+ int32 consttypmod; /* typmod value, if any */
+ Oid constcollid; /* OID of collation, or InvalidOid if none */
int constlen; /* typlen of the constant's datatype */
Datum constvalue; /* the constant's value */
bool constisnull; /* whether the constant is null (if true,
* If true, then all the information is stored
* in the Datum. If false, then the Datum
* contains a pointer to the information. */
+ int location; /* token location, or -1 if unknown */
} Const;
-/* ----------------
+/*
* Param
- * paramkind - specifies the kind of parameter. The possible values
- * for this field are specified in "params.h", and they are:
*
- * PARAM_NAMED: The parameter has a name, i.e. something
- * like `$.salary' or `$.foobar'.
- * In this case field `paramname' must be a valid name.
+ * paramkind specifies the kind of parameter. The possible values
+ * for this field are:
*
- * PARAM_NUM: The parameter has only a numeric identifier,
- * i.e. something like `$1', `$2' etc.
- * The number is contained in the `paramid' field.
+ * PARAM_EXTERN: The parameter value is supplied from outside the plan.
+ * Such parameters are numbered from 1 to n.
*
- * PARAM_EXEC: The parameter is an internal executor parameter.
- * It has a number contained in the `paramid' field.
- * ----------------
+ * PARAM_EXEC: The parameter is an internal executor parameter, used
+ * for passing values into and out of sub-queries or from
+ * nestloop joins to their inner scans.
+ * For historical reasons, such parameters are numbered from 0.
+ * These numbers are independent of PARAM_EXTERN numbers.
+ *
+ * PARAM_SUBLINK: The parameter represents an output column of a SubLink
+ * node's sub-select. The column number is contained in the
+ * `paramid' field. (This type of Param is converted to
+ * PARAM_EXEC during planning.)
+ *
+ * PARAM_MULTIEXPR: Like PARAM_SUBLINK, the parameter represents an
+ * output column of a SubLink node's sub-select, but here, the
+ * SubLink is always a MULTIEXPR SubLink. The high-order 16 bits
+ * of the `paramid' field contain the SubLink's subLinkId, and
+ * the low-order 16 bits contain the column number. (This type
+ * of Param is also converted to PARAM_EXEC during planning.)
*/
+typedef enum ParamKind
+{
+ PARAM_EXTERN,
+ PARAM_EXEC,
+ PARAM_SUBLINK,
+ PARAM_MULTIEXPR
+} ParamKind;
+
typedef struct Param
{
Expr xpr;
- int paramkind; /* kind of parameter. See above */
- AttrNumber paramid; /* numeric ID for parameter ("$1") */
- char *paramname; /* name for parameter ("$.foo") */
- Oid paramtype; /* PG_TYPE OID of parameter's datatype */
+ ParamKind paramkind; /* kind of parameter. See above */
+ int paramid; /* numeric ID for parameter */
+ Oid paramtype; /* pg_type OID of parameter's datatype */
+ int32 paramtypmod; /* typmod value, if known */
+ Oid paramcollid; /* OID of collation, or InvalidOid if none */
+ int location; /* token location, or -1 if unknown */
} Param;
/*
* Aggref
+ *
+ * The aggregate's args list is a targetlist, ie, a list of TargetEntry nodes.
+ *
+ * For a normal (non-ordered-set) aggregate, the non-resjunk TargetEntries
+ * represent the aggregate's regular arguments (if any) and resjunk TLEs can
+ * be added at the end to represent ORDER BY expressions that are not also
+ * arguments. As in a top-level Query, the TLEs can be marked with
+ * ressortgroupref indexes to let them be referenced by SortGroupClause
+ * entries in the aggorder and/or aggdistinct lists. This represents ORDER BY
+ * and DISTINCT operations to be applied to the aggregate input rows before
+ * they are passed to the transition function. The grammar only allows a
+ * simple "DISTINCT" specifier for the arguments, but we use the full
+ * query-level representation to allow more code sharing.
+ *
+ * For an ordered-set aggregate, the args list represents the WITHIN GROUP
+ * (aggregated) arguments, all of which will be listed in the aggorder list.
+ * DISTINCT is not supported in this case, so aggdistinct will be NIL.
+ * The direct arguments appear in aggdirectargs (as a list of plain
+ * expressions, not TargetEntry nodes).
*/
typedef struct Aggref
{
Expr xpr;
Oid aggfnoid; /* pg_proc Oid of the aggregate */
Oid aggtype; /* type Oid of result of the aggregate */
- Expr *target; /* expression we are aggregating on */
+ Oid aggcollid; /* OID of collation of result */
+ Oid inputcollid; /* OID of collation that function should use */
+ List *aggdirectargs; /* direct arguments, if an ordered-set agg */
+ List *args; /* aggregated arguments and sort expressions */
+ List *aggorder; /* ORDER BY (list of SortGroupClause) */
+ List *aggdistinct; /* DISTINCT (list of SortGroupClause) */
+ Expr *aggfilter; /* FILTER expression, if any */
+ bool aggstar; /* TRUE if argument list was really '*' */
+ bool aggvariadic; /* true if variadic arguments have been
+ * combined into an array last argument */
+ char aggkind; /* aggregate kind (see pg_aggregate.h) */
Index agglevelsup; /* > 0 if agg belongs to outer query */
- bool aggstar; /* TRUE if argument was really '*' */
- bool aggdistinct; /* TRUE if it's agg(DISTINCT ...) */
+ int location; /* token location, or -1 if unknown */
} Aggref;
+/*
+ * GroupingFunc
+ *
+ * A GroupingFunc is a GROUPING(...) expression, which behaves in many ways
+ * like an aggregate function (e.g. it "belongs" to a specific query level,
+ * which might not be the one immediately containing it), but also differs in
+ * an important respect: it never evaluates its arguments, they merely
+ * designate expressions from the GROUP BY clause of the query level to which
+ * it belongs.
+ *
+ * The spec defines the evaluation of GROUPING() purely by syntactic
+ * replacement, but we make it a real expression for optimization purposes so
+ * that one Agg node can handle multiple grouping sets at once. Evaluating the
+ * result only needs the column positions to check against the grouping set
+ * being projected. However, for EXPLAIN to produce meaningful output, we have
+ * to keep the original expressions around, since expression deparse does not
+ * give us any feasible way to get at the GROUP BY clause.
+ *
+ * Also, we treat two GroupingFunc nodes as equal if they have equal arguments
+ * lists and agglevelsup, without comparing the refs and cols annotations.
+ *
+ * In raw parse output we have only the args list; parse analysis fills in the
+ * refs list, and the planner fills in the cols list.
+ */
+typedef struct GroupingFunc
+{
+ Expr xpr;
+ List *args; /* arguments, not evaluated but kept for
+ * benefit of EXPLAIN etc. */
+ List *refs; /* ressortgrouprefs of arguments */
+ List *cols; /* actual column positions set by planner */
+ Index agglevelsup; /* same as Aggref.agglevelsup */
+ int location; /* token location */
+} GroupingFunc;
+
+/*
+ * WindowFunc
+ */
+typedef struct WindowFunc
+{
+ Expr xpr;
+ Oid winfnoid; /* pg_proc Oid of the function */
+ Oid wintype; /* type Oid of result of the window function */
+ Oid wincollid; /* OID of collation of result */
+ Oid inputcollid; /* OID of collation that function should use */
+ List *args; /* arguments to the window function */
+ Expr *aggfilter; /* FILTER expression, if any */
+ Index winref; /* index of associated WindowClause */
+ bool winstar; /* TRUE if argument list was really '*' */
+ bool winagg; /* is function a simple aggregate? */
+ int location; /* token location, or -1 if unknown */
+} WindowFunc;
+
/* ----------------
* ArrayRef: describes an array subscripting operation
*
* entire new modified array value.
*
* If reflowerindexpr = NIL, then we are fetching or storing a single array
- * element at the subscripts given by refupperindexpr. Otherwise we are
+ * element at the subscripts given by refupperindexpr. Otherwise we are
* fetching or storing an array slice, that is a rectangular subarray
* with lower and upper bounds given by the index expressions.
* reflowerindexpr must be the same length as refupperindexpr when it
* is not NIL.
*
- * Note: refrestype is NOT the element type, but the array type,
- * when doing subarray fetch or either type of store.
+ * Note: the result datatype is the element type when fetching a single
+ * element; but it is the array type when doing subarray fetch or either
+ * type of store.
+ *
+ * Note: for the cases where an array is returned, if refexpr yields a R/W
+ * expanded array, then the implementation is allowed to modify that object
+ * in-place and return the same object.)
* ----------------
*/
typedef struct ArrayRef
{
Expr xpr;
- Oid refrestype; /* type of the result of the ArrayRef
- * operation */
Oid refarraytype; /* type of the array proper */
Oid refelemtype; /* type of the array elements */
+ int32 reftypmod; /* typmod of the array (and elements too) */
+ Oid refcollid; /* OID of collation, or InvalidOid if none */
List *refupperindexpr;/* expressions that evaluate to upper array
* indexes */
List *reflowerindexpr;/* expressions that evaluate to lower array
} CoercionContext;
/*
- * CoercionForm - information showing how to display a function-call node
+ * CoercionForm - how to display a node that could have come from a cast
+ *
+ * NB: equal() ignores CoercionForm fields, therefore this *must* not carry
+ * any semantically significant information. We need that behavior so that
+ * the planner will consider equivalent implicit and explicit casts to be
+ * equivalent. In cases where those actually behave differently, the coercion
+ * function's arguments will be different.
*/
typedef enum CoercionForm
{
COERCE_EXPLICIT_CALL, /* display as a function call */
COERCE_EXPLICIT_CAST, /* display as an explicit cast */
- COERCE_IMPLICIT_CAST, /* implicit cast, so hide it */
- COERCE_DONTCARE /* special case for planner */
+ COERCE_IMPLICIT_CAST /* implicit cast, so hide it */
} CoercionForm;
/*
Oid funcid; /* PG_PROC OID of the function */
Oid funcresulttype; /* PG_TYPE OID of result value */
bool funcretset; /* true if function returns set */
+ bool funcvariadic; /* true if variadic arguments have been
+ * combined into an array last argument */
CoercionForm funcformat; /* how to display this function call */
+ Oid funccollid; /* OID of collation of result */
+ Oid inputcollid; /* OID of collation that function should use */
List *args; /* arguments to the function */
+ int location; /* token location, or -1 if unknown */
} FuncExpr;
+/*
+ * NamedArgExpr - a named argument of a function
+ *
+ * This node type can only appear in the args list of a FuncCall or FuncExpr
+ * node. We support pure positional call notation (no named arguments),
+ * named notation (all arguments are named), and mixed notation (unnamed
+ * arguments followed by named ones).
+ *
+ * Parse analysis sets argnumber to the positional index of the argument,
+ * but doesn't rearrange the argument list.
+ *
+ * The planner will convert argument lists to pure positional notation
+ * during expression preprocessing, so execution never sees a NamedArgExpr.
+ */
+typedef struct NamedArgExpr
+{
+ Expr xpr;
+ Expr *arg; /* the argument expression */
+ char *name; /* the name */
+ int argnumber; /* argument's number in positional notation */
+ int location; /* argument name location, or -1 if unknown */
+} NamedArgExpr;
+
/*
* OpExpr - expression node for an operator invocation
*
*
* Note that opfuncid is not necessarily filled in immediately on creation
* of the node. The planner makes sure it is valid before passing the node
- * tree to the executor, but during parsing/planning opfuncid is typically 0.
+ * tree to the executor, but during parsing/planning opfuncid can be 0.
*/
typedef struct OpExpr
{
Oid opfuncid; /* PG_PROC OID of underlying function */
Oid opresulttype; /* PG_TYPE OID of result value */
bool opretset; /* true if operator returns set */
+ Oid opcollid; /* OID of collation of result */
+ Oid inputcollid; /* OID of collation that operator should use */
List *args; /* arguments to the operator (1 or 2) */
+ int location; /* token location, or -1 if unknown */
} OpExpr;
/*
*/
typedef OpExpr DistinctExpr;
+/*
+ * NullIfExpr - a NULLIF expression
+ *
+ * Like DistinctExpr, this is represented the same as an OpExpr referencing
+ * the "=" operator for x and y.
+ */
+typedef OpExpr NullIfExpr;
+
/*
* ScalarArrayOpExpr - expression node for "scalar op ANY/ALL (array)"
*
* with OR or AND (for ANY or ALL respectively). The node representation
* is almost the same as for the underlying operator, but we need a useOr
* flag to remember whether it's ANY or ALL, and we don't have to store
- * the result type because it must be boolean.
+ * the result type (or the collation) because it must be boolean.
*/
typedef struct ScalarArrayOpExpr
{
Oid opno; /* PG_OPERATOR OID of the operator */
Oid opfuncid; /* PG_PROC OID of underlying function */
bool useOr; /* true for ANY, false for ALL */
+ Oid inputcollid; /* OID of collation that operator should use */
List *args; /* the scalar and array operands */
+ int location; /* token location, or -1 if unknown */
} ScalarArrayOpExpr;
/*
* BoolExpr - expression node for the basic Boolean operators AND, OR, NOT
*
* Notice the arguments are given as a List. For NOT, of course the list
- * must always have exactly one element. For AND and OR, the executor can
- * handle any number of arguments. The parser treats AND and OR as binary
- * and so it only produces two-element lists, but the optimizer will flatten
- * trees of AND and OR nodes to produce longer lists when possible.
+ * must always have exactly one element. For AND and OR, there can be two
+ * or more arguments.
*/
typedef enum BoolExprType
{
Expr xpr;
BoolExprType boolop;
List *args; /* arguments to this expression */
+ int location; /* token location, or -1 if unknown */
} BoolExpr;
-/* ----------------
+/*
* SubLink
*
* A SubLink represents a subselect appearing in an expression, and in some
- * cases also the combining operator(s) just above it. The subLinkType
+ * cases also the combining operator(s) just above it. The subLinkType
* indicates the form of the expression represented:
* EXISTS_SUBLINK EXISTS(SELECT ...)
* ALL_SUBLINK (lefthand) op ALL (SELECT ...)
* ANY_SUBLINK (lefthand) op ANY (SELECT ...)
- * MULTIEXPR_SUBLINK (lefthand) op (SELECT ...)
+ * ROWCOMPARE_SUBLINK (lefthand) op (SELECT ...)
* EXPR_SUBLINK (SELECT with single targetlist item ...)
+ * MULTIEXPR_SUBLINK (SELECT with multiple targetlist items ...)
* ARRAY_SUBLINK ARRAY(SELECT with single targetlist item ...)
- * For ALL, ANY, and MULTIEXPR, the lefthand is a list of expressions of the
- * same length as the subselect's targetlist. MULTIEXPR will *always* have
+ * CTE_SUBLINK WITH query (never actually part of an expression)
+ * For ALL, ANY, and ROWCOMPARE, the lefthand is a list of expressions of the
+ * same length as the subselect's targetlist. ROWCOMPARE will *always* have
* a list with more than one entry; if the subselect has just one target
* then the parser will create an EXPR_SUBLINK instead (and any operator
- * above the subselect will be represented separately). Note that both
- * MULTIEXPR and EXPR require the subselect to deliver only one row.
+ * above the subselect will be represented separately).
+ * ROWCOMPARE, EXPR, and MULTIEXPR require the subselect to deliver at most
+ * one row (if it returns no rows, the result is NULL).
+ * ALL, ANY, and ROWCOMPARE require the combining operators to deliver boolean
+ * results. ALL and ANY combine the per-row results using AND and OR
+ * semantics respectively.
* ARRAY requires just one target column, and creates an array of the target
- * column's type using one or more rows resulting from the subselect.
- * ALL, ANY, and MULTIEXPR require the combining operators to deliver boolean
- * results. These are reduced to one result per row using OR or AND semantics
- * depending on the "useOr" flag. ALL and ANY combine the per-row results
- * using AND and OR semantics respectively.
+ * column's type using any number of rows resulting from the subselect.
*
* SubLink is classed as an Expr node, but it is not actually executable;
* it must be replaced in the expression tree by a SubPlan node during
* planning.
*
- * NOTE: in the raw output of gram.y, lefthand contains a list of raw
- * expressions; useOr and operOids are not filled in yet. Also, subselect
- * is a raw parsetree. During parse analysis, the parser transforms the
- * lefthand expression list using normal expression transformation rules.
- * It fills operOids with the OIDs representing the specific operator(s)
- * to apply to each pair of lefthand and targetlist expressions.
- * And subselect is transformed to a Query. This is the representation
- * seen in saved rules and in the rewriter.
- *
- * In EXISTS, EXPR, and ARRAY SubLinks, lefthand, operName, and operOids are
- * unused and are always NIL. useOr is not significant either for these
- * sublink types.
- * ----------------
+ * NOTE: in the raw output of gram.y, testexpr contains just the raw form
+ * of the lefthand expression (if any), and operName is the String name of
+ * the combining operator. Also, subselect is a raw parsetree. During parse
+ * analysis, the parser transforms testexpr into a complete boolean expression
+ * that compares the lefthand value(s) to PARAM_SUBLINK nodes representing the
+ * output columns of the subselect. And subselect is transformed to a Query.
+ * This is the representation seen in saved rules and in the rewriter.
+ *
+ * In EXISTS, EXPR, MULTIEXPR, and ARRAY SubLinks, testexpr and operName
+ * are unused and are always null.
+ *
+ * subLinkId is currently used only for MULTIEXPR SubLinks, and is zero in
+ * other SubLinks. This number identifies different multiple-assignment
+ * subqueries within an UPDATE statement's SET list. It is unique only
+ * within a particular targetlist. The output column(s) of the MULTIEXPR
+ * are referenced by PARAM_MULTIEXPR Params appearing elsewhere in the tlist.
+ *
+ * The CTE_SUBLINK case never occurs in actual SubLink nodes, but it is used
+ * in SubPlans generated for WITH subqueries.
*/
typedef enum SubLinkType
{
EXISTS_SUBLINK,
ALL_SUBLINK,
ANY_SUBLINK,
- MULTIEXPR_SUBLINK,
+ ROWCOMPARE_SUBLINK,
EXPR_SUBLINK,
- ARRAY_SUBLINK
+ MULTIEXPR_SUBLINK,
+ ARRAY_SUBLINK,
+ CTE_SUBLINK /* for SubPlans only */
} SubLinkType;
typedef struct SubLink
{
Expr xpr;
- SubLinkType subLinkType; /* EXISTS, ALL, ANY, MULTIEXPR, EXPR */
- bool useOr; /* TRUE to combine column results with "OR"
- * not "AND" */
- List *lefthand; /* list of outer-query expressions on the left */
+ SubLinkType subLinkType; /* see above */
+ int subLinkId; /* ID (1..n); 0 if not MULTIEXPR */
+ Node *testexpr; /* outer-query test for ALL/ANY/ROWCOMPARE */
List *operName; /* originally specified operator name */
- List *operOids; /* OIDs of actual combining operators */
- Node *subselect; /* subselect as Query* or parsetree */
+ Node *subselect; /* subselect as Query* or raw parsetree */
+ int location; /* token location, or -1 if unknown */
} SubLink;
/*
* SubPlan - executable expression node for a subplan (sub-SELECT)
*
* The planner replaces SubLink nodes in expression trees with SubPlan
- * nodes after it has finished planning the subquery. SubPlan contains
- * a sub-plantree and rtable instead of a sub-Query.
- *
- * In an ordinary subplan, "exprs" points to a list of executable expressions
- * (OpExpr trees) for the combining operators; their left-hand arguments are
- * the original lefthand expressions, and their right-hand arguments are
- * PARAM_EXEC Param nodes representing the outputs of the sub-select.
- * (NOTE: runtime coercion functions may be inserted as well.) But if the
- * sub-select becomes an initplan rather than a subplan, these executable
- * expressions are part of the outer plan's expression tree (and the SubPlan
- * node itself is not). In this case "exprs" is NIL to avoid duplication.
+ * nodes after it has finished planning the subquery. SubPlan references
+ * a sub-plantree stored in the subplans list of the toplevel PlannedStmt.
+ * (We avoid a direct link to make it easier to copy expression trees
+ * without causing multiple processing of the subplan.)
+ *
+ * In an ordinary subplan, testexpr points to an executable expression
+ * (OpExpr, an AND/OR tree of OpExprs, or RowCompareExpr) for the combining
+ * operator(s); the left-hand arguments are the original lefthand expressions,
+ * and the right-hand arguments are PARAM_EXEC Param nodes representing the
+ * outputs of the sub-select. (NOTE: runtime coercion functions may be
+ * inserted as well.) This is just the same expression tree as testexpr in
+ * the original SubLink node, but the PARAM_SUBLINK nodes are replaced by
+ * suitably numbered PARAM_EXEC nodes.
+ *
+ * If the sub-select becomes an initplan rather than a subplan, the executable
+ * expression is part of the outer plan's expression tree (and the SubPlan
+ * node itself is not, but rather is found in the outer plan's initPlan
+ * list). In this case testexpr is NULL to avoid duplication.
*
* The planner also derives lists of the values that need to be passed into
- * and out of the subplan. Input values are represented as a list "args" of
+ * and out of the subplan. Input values are represented as a list "args" of
* expressions to be evaluated in the outer-query context (currently these
* args are always just Vars, but in principle they could be any expression).
* The values are assigned to the global PARAM_EXEC params indexed by parParam
* is an initplan; they are listed in order by sub-select output column
* position. (parParam and setParam are integer Lists, not Bitmapsets,
* because their ordering is significant.)
+ *
+ * Also, the planner computes startup and per-call costs for use of the
+ * SubPlan. Note that these include the cost of the subquery proper,
+ * evaluation of the testexpr if any, and any hashtable management overhead.
*/
typedef struct SubPlan
{
Expr xpr;
/* Fields copied from original SubLink: */
- SubLinkType subLinkType; /* EXISTS, ALL, ANY, MULTIEXPR, EXPR */
- bool useOr; /* TRUE to combine column results with "OR"
- * not "AND" */
- /* The combining operators, transformed to executable expressions: */
- List *exprs; /* list of OpExpr expression trees */
+ SubLinkType subLinkType; /* see above */
+ /* The combining operators, transformed to an executable expression: */
+ Node *testexpr; /* OpExpr or RowCompareExpr expression tree */
List *paramIds; /* IDs of Params embedded in the above */
- /* Note: paramIds has a one-to-one correspondence to the exprs list */
- /* The subselect, transformed to a Plan: */
- struct Plan *plan; /* subselect plan itself */
- int plan_id; /* dummy thing because of we haven't equal
- * funcs for plan nodes... actually, we could
- * put *plan itself somewhere else (TopPlan
- * node ?)... */
- List *rtable; /* range table for subselect */
+ /* Identification of the Plan tree to use: */
+ int plan_id; /* Index (from 1) in PlannedStmt.subplans */
+ /* Identification of the SubPlan for EXPLAIN and debugging purposes: */
+ char *plan_name; /* A name assigned during planning */
+ /* Extra data useful for determining subplan's output type: */
+ Oid firstColType; /* Type of first column of subplan result */
+ int32 firstColTypmod; /* Typmod of first column of subplan result */
+ Oid firstColCollation; /* Collation of first column of
+ * subplan result */
/* Information about execution strategy: */
bool useHashTable; /* TRUE to store subselect output in a hash
* table (implies we are doing "IN") */
* Params for parent plan */
List *parParam; /* indices of input Params from parent plan */
List *args; /* exprs to pass as parParam values */
+ /* Estimated execution costs: */
+ Cost startup_cost; /* one-time setup cost */
+ Cost per_call_cost; /* cost for each subplan evaluation */
} SubPlan;
+/*
+ * AlternativeSubPlan - expression node for a choice among SubPlans
+ *
+ * The subplans are given as a List so that the node definition need not
+ * change if there's ever more than two alternatives. For the moment,
+ * though, there are always exactly two; and the first one is the fast-start
+ * plan.
+ */
+typedef struct AlternativeSubPlan
+{
+ Expr xpr;
+ List *subplans; /* SubPlan(s) with equivalent results */
+} AlternativeSubPlan;
+
/* ----------------
* FieldSelect
*
Oid resulttype; /* type of the field (result type of this
* node) */
int32 resulttypmod; /* output typmod (usually -1) */
+ Oid resultcollid; /* OID of collation of the field */
} FieldSelect;
/* ----------------
* portion of a column.
*
* A single FieldStore can actually represent updates of several different
- * fields. The parser only generates FieldStores with single-element lists,
+ * fields. The parser only generates FieldStores with single-element lists,
* but the planner will collapse multiple updates of the same base column
* into one FieldStore.
* ----------------
List *newvals; /* new value(s) for field(s) */
List *fieldnums; /* integer list of field attnums */
Oid resulttype; /* type of result (same as type of arg) */
- /* Like RowExpr, we deliberately omit a typmod here */
+ /* Like RowExpr, we deliberately omit a typmod and collation here */
} FieldStore;
/* ----------------
Expr *arg; /* input expression */
Oid resulttype; /* output type of coercion expression */
int32 resulttypmod; /* output typmod (usually -1) */
+ Oid resultcollid; /* OID of collation, or InvalidOid if none */
CoercionForm relabelformat; /* how to display this node */
+ int location; /* token location, or -1 if unknown */
} RelabelType;
+/* ----------------
+ * CoerceViaIO
+ *
+ * CoerceViaIO represents a type coercion between two types whose textual
+ * representations are compatible, implemented by invoking the source type's
+ * typoutput function then the destination type's typinput function.
+ * ----------------
+ */
+
+typedef struct CoerceViaIO
+{
+ Expr xpr;
+ Expr *arg; /* input expression */
+ Oid resulttype; /* output type of coercion */
+ /* output typmod is not stored, but is presumed -1 */
+ Oid resultcollid; /* OID of collation, or InvalidOid if none */
+ CoercionForm coerceformat; /* how to display this node */
+ int location; /* token location, or -1 if unknown */
+} CoerceViaIO;
+
+/* ----------------
+ * ArrayCoerceExpr
+ *
+ * ArrayCoerceExpr represents a type coercion from one array type to another,
+ * which is implemented by applying the indicated element-type coercion
+ * function to each element of the source array. If elemfuncid is InvalidOid
+ * then the element types are binary-compatible, but the coercion still
+ * requires some effort (we have to fix the element type ID stored in the
+ * array header).
+ * ----------------
+ */
+
+typedef struct ArrayCoerceExpr
+{
+ Expr xpr;
+ Expr *arg; /* input expression (yields an array) */
+ Oid elemfuncid; /* OID of element coercion function, or 0 */
+ Oid resulttype; /* output type of coercion (an array type) */
+ int32 resulttypmod; /* output typmod (also element typmod) */
+ Oid resultcollid; /* OID of collation, or InvalidOid if none */
+ bool isExplicit; /* conversion semantics flag to pass to func */
+ CoercionForm coerceformat; /* how to display this node */
+ int location; /* token location, or -1 if unknown */
+} ArrayCoerceExpr;
+
/* ----------------
* ConvertRowtypeExpr
*
Expr xpr;
Expr *arg; /* input expression */
Oid resulttype; /* output type (always a composite type) */
- /* result typmod is not stored, but must be -1; see RowExpr comments */
+ /* Like RowExpr, we deliberately omit a typmod and collation here */
CoercionForm convertformat; /* how to display this node */
+ int location; /* token location, or -1 if unknown */
} ConvertRowtypeExpr;
+/*----------
+ * CollateExpr - COLLATE
+ *
+ * The planner replaces CollateExpr with RelabelType during expression
+ * preprocessing, so execution never sees a CollateExpr.
+ *----------
+ */
+typedef struct CollateExpr
+{
+ Expr xpr;
+ Expr *arg; /* input expression */
+ Oid collOid; /* collation's OID */
+ int location; /* token location, or -1 if unknown */
+} CollateExpr;
+
/*----------
* CaseExpr - a CASE expression
*
* and the testexpr in the second case.
*
* In the raw grammar output for the second form, the condition expressions
- * of the WHEN clauses are just the comparison values. Parse analysis
+ * of the WHEN clauses are just the comparison values. Parse analysis
* converts these to valid boolean expressions of the form
* CaseTestExpr '=' compexpr
* where the CaseTestExpr node is a placeholder that emits the correct
{
Expr xpr;
Oid casetype; /* type of expression result */
+ Oid casecollid; /* OID of collation, or InvalidOid if none */
Expr *arg; /* implicit equality comparison argument */
List *args; /* the arguments (list of WHEN clauses) */
Expr *defresult; /* the default result (ELSE clause) */
+ int location; /* token location, or -1 if unknown */
} CaseExpr;
/*
Expr xpr;
Expr *expr; /* condition expression */
Expr *result; /* substitution result */
+ int location; /* token location, or -1 if unknown */
} CaseWhen;
/*
Expr xpr;
Oid typeId; /* type for substituted value */
int32 typeMod; /* typemod for substituted value */
+ Oid collation; /* collation for the substituted value */
} CaseTestExpr;
/*
{
Expr xpr;
Oid array_typeid; /* type of expression result */
+ Oid array_collid; /* OID of collation, or InvalidOid if none */
Oid element_typeid; /* common type of array elements */
List *elements; /* the array elements or sub-arrays */
bool multidims; /* true if elements are sub-arrays */
+ int location; /* token location, or -1 if unknown */
} ArrayExpr;
/*
*
* Note: the list of fields must have a one-for-one correspondence with
* physical fields of the associated rowtype, although it is okay for it
- * to be shorter than the rowtype. That is, the N'th list element must
+ * to be shorter than the rowtype. That is, the N'th list element must
* match up with the N'th physical field. When the N'th physical field
* is a dropped column (attisdropped) then the N'th list element can just
- * be a NULL constant. (This case can only occur for named composite types,
+ * be a NULL constant. (This case can only occur for named composite types,
* not RECORD types, since those are built from the RowExpr itself rather
* than vice versa.) It is important not to assume that length(args) is
* the same as the number of columns logically present in the rowtype.
+ *
+ * colnames provides field names in cases where the names can't easily be
+ * obtained otherwise. Names *must* be provided if row_typeid is RECORDOID.
+ * If row_typeid identifies a known composite type, colnames can be NIL to
+ * indicate the type's cataloged field names apply. Note that colnames can
+ * be non-NIL even for a composite type, and typically is when the RowExpr
+ * was created by expanding a whole-row Var. This is so that we can retain
+ * the column alias names of the RTE that the Var referenced (which would
+ * otherwise be very difficult to extract from the parsetree). Like the
+ * args list, colnames is one-for-one with physical fields of the rowtype.
*/
typedef struct RowExpr
{
* Note: we deliberately do NOT store a typmod. Although a typmod will be
* associated with specific RECORD types at runtime, it will differ for
* different backends, and so cannot safely be stored in stored
- * parsetrees. We must assume typmod -1 for a RowExpr node.
+ * parsetrees. We must assume typmod -1 for a RowExpr node.
+ *
+ * We don't need to store a collation either. The result type is
+ * necessarily composite, and composite types never have a collation.
*/
CoercionForm row_format; /* how to display this node */
+ List *colnames; /* list of String, or NIL */
+ int location; /* token location, or -1 if unknown */
} RowExpr;
+/*
+ * RowCompareExpr - row-wise comparison, such as (a, b) <= (1, 2)
+ *
+ * We support row comparison for any operator that can be determined to
+ * act like =, <>, <, <=, >, or >= (we determine this by looking for the
+ * operator in btree opfamilies). Note that the same operator name might
+ * map to a different operator for each pair of row elements, since the
+ * element datatypes can vary.
+ *
+ * A RowCompareExpr node is only generated for the < <= > >= cases;
+ * the = and <> cases are translated to simple AND or OR combinations
+ * of the pairwise comparisons. However, we include = and <> in the
+ * RowCompareType enum for the convenience of parser logic.
+ */
+typedef enum RowCompareType
+{
+ /* Values of this enum are chosen to match btree strategy numbers */
+ ROWCOMPARE_LT = 1, /* BTLessStrategyNumber */
+ ROWCOMPARE_LE = 2, /* BTLessEqualStrategyNumber */
+ ROWCOMPARE_EQ = 3, /* BTEqualStrategyNumber */
+ ROWCOMPARE_GE = 4, /* BTGreaterEqualStrategyNumber */
+ ROWCOMPARE_GT = 5, /* BTGreaterStrategyNumber */
+ ROWCOMPARE_NE = 6 /* no such btree strategy */
+} RowCompareType;
+
+typedef struct RowCompareExpr
+{
+ Expr xpr;
+ RowCompareType rctype; /* LT LE GE or GT, never EQ or NE */
+ List *opnos; /* OID list of pairwise comparison ops */
+ List *opfamilies; /* OID list of containing operator families */
+ List *inputcollids; /* OID list of collations for comparisons */
+ List *largs; /* the left-hand input arguments */
+ List *rargs; /* the right-hand input arguments */
+} RowCompareExpr;
+
/*
* CoalesceExpr - a COALESCE expression
*/
{
Expr xpr;
Oid coalescetype; /* type of expression result */
+ Oid coalescecollid; /* OID of collation, or InvalidOid if none */
List *args; /* the arguments */
+ int location; /* token location, or -1 if unknown */
} CoalesceExpr;
/*
{
Expr xpr;
Oid minmaxtype; /* common type of arguments and result */
+ Oid minmaxcollid; /* OID of collation of result */
+ Oid inputcollid; /* OID of collation that function should use */
MinMaxOp op; /* function to execute */
List *args; /* the arguments */
+ int location; /* token location, or -1 if unknown */
} MinMaxExpr;
/*
- * NullIfExpr - a NULLIF expression
+ * XmlExpr - various SQL/XML functions requiring special grammar productions
*
- * Like DistinctExpr, this is represented the same as an OpExpr referencing
- * the "=" operator for x and y.
+ * 'name' carries the "NAME foo" argument (already XML-escaped).
+ * 'named_args' and 'arg_names' represent an xml_attribute list.
+ * 'args' carries all other arguments.
+ *
+ * Note: result type/typmod/collation are not stored, but can be deduced
+ * from the XmlExprOp. The type/typmod fields are just used for display
+ * purposes, and are NOT necessarily the true result type of the node.
*/
-typedef OpExpr NullIfExpr;
+typedef enum XmlExprOp
+{
+ IS_XMLCONCAT, /* XMLCONCAT(args) */
+ IS_XMLELEMENT, /* XMLELEMENT(name, xml_attributes, args) */
+ IS_XMLFOREST, /* XMLFOREST(xml_attributes) */
+ IS_XMLPARSE, /* XMLPARSE(text, is_doc, preserve_ws) */
+ IS_XMLPI, /* XMLPI(name [, args]) */
+ IS_XMLROOT, /* XMLROOT(xml, version, standalone) */
+ IS_XMLSERIALIZE, /* XMLSERIALIZE(is_document, xmlval) */
+ IS_DOCUMENT /* xmlval IS DOCUMENT */
+} XmlExprOp;
+
+typedef enum
+{
+ XMLOPTION_DOCUMENT,
+ XMLOPTION_CONTENT
+} XmlOptionType;
+
+typedef struct XmlExpr
+{
+ Expr xpr;
+ XmlExprOp op; /* xml function ID */
+ char *name; /* name in xml(NAME foo ...) syntaxes */
+ List *named_args; /* non-XML expressions for xml_attributes */
+ List *arg_names; /* parallel list of Value strings */
+ List *args; /* list of expressions */
+ XmlOptionType xmloption; /* DOCUMENT or CONTENT */
+ Oid type; /* target type/typmod for XMLSERIALIZE */
+ int32 typmod;
+ int location; /* token location, or -1 if unknown */
+} XmlExpr;
/* ----------------
* NullTest
*
* NullTest represents the operation of testing a value for NULLness.
- * Currently, we only support scalar input values, but eventually a
- * row-constructor input should be supported.
* The appropriate test is performed and returned as a boolean Datum.
+ *
+ * NOTE: the semantics of this for rowtype inputs are noticeably different
+ * from the scalar case. We provide an "argisrow" flag to reflect that.
* ----------------
*/
Expr xpr;
Expr *arg; /* input expression */
NullTestType nulltesttype; /* IS NULL, IS NOT NULL */
+ bool argisrow; /* T if input is of a composite type */
+ int location; /* token location, or -1 if unknown */
} NullTest;
/*
Expr xpr;
Expr *arg; /* input expression */
BoolTestType booltesttype; /* test type */
+ int location; /* token location, or -1 if unknown */
} BooleanTest;
/*
*
* CoerceToDomain represents the operation of coercing a value to a domain
* type. At runtime (and not before) the precise set of constraints to be
- * checked will be determined. If the value passes, it is returned as the
- * result; if not, an error is raised. Note that this is equivalent to
+ * checked will be determined. If the value passes, it is returned as the
+ * result; if not, an error is raised. Note that this is equivalent to
* RelabelType in the scenario where no constraints are applied.
*/
typedef struct CoerceToDomain
Expr *arg; /* input expression */
Oid resulttype; /* domain type ID (result type) */
int32 resulttypmod; /* output typmod (currently always -1) */
+ Oid resultcollid; /* OID of collation, or InvalidOid if none */
CoercionForm coercionformat; /* how to display this node */
+ int location; /* token location, or -1 if unknown */
} CoerceToDomain;
/*
* Placeholder node for the value to be processed by a domain's check
- * constraint. This is effectively like a Param, but can be implemented more
+ * constraint. This is effectively like a Param, but can be implemented more
* simply since we need only one replacement value at a time.
*
- * Note: the typeId/typeMod will be set from the domain's base type, not
- * the domain itself. This is because we shouldn't consider the value to
- * be a member of the domain if we haven't yet checked its constraints.
+ * Note: the typeId/typeMod/collation will be set from the domain's base type,
+ * not the domain itself. This is because we shouldn't consider the value
+ * to be a member of the domain if we haven't yet checked its constraints.
*/
typedef struct CoerceToDomainValue
{
Expr xpr;
Oid typeId; /* type for substituted value */
int32 typeMod; /* typemod for substituted value */
+ Oid collation; /* collation for the substituted value */
+ int location; /* token location, or -1 if unknown */
} CoerceToDomainValue;
/*
* Placeholder node for a DEFAULT marker in an INSERT or UPDATE command.
*
* This is not an executable expression: it must be replaced by the actual
- * column default expression during rewriting. But it is convenient to
+ * column default expression during rewriting. But it is convenient to
* treat it as an expression node during parsing and rewriting.
*/
typedef struct SetToDefault
Expr xpr;
Oid typeId; /* type for substituted value */
int32 typeMod; /* typemod for substituted value */
+ Oid collation; /* collation for the substituted value */
+ int location; /* token location, or -1 if unknown */
} SetToDefault;
+/*
+ * Node representing [WHERE] CURRENT OF cursor_name
+ *
+ * CURRENT OF is a bit like a Var, in that it carries the rangetable index
+ * of the target relation being constrained; this aids placing the expression
+ * correctly during planning. We can assume however that its "levelsup" is
+ * always zero, due to the syntactic constraints on where it can appear.
+ *
+ * The referenced cursor can be represented either as a hardwired string
+ * or as a reference to a run-time parameter of type REFCURSOR. The latter
+ * case is for the convenience of plpgsql.
+ */
+typedef struct CurrentOfExpr
+{
+ Expr xpr;
+ Index cvarno; /* RT index of target relation */
+ char *cursor_name; /* name of referenced cursor, or NULL */
+ int cursor_param; /* refcursor parameter number, or 0 */
+} CurrentOfExpr;
+
+/*
+ * InferenceElem - an element of a unique index inference specification
+ *
+ * This mostly matches the structure of IndexElems, but having a dedicated
+ * primnode allows for a clean separation between the use of index parameters
+ * by utility commands, and this node.
+ */
+typedef struct InferenceElem
+{
+ Expr xpr;
+ Node *expr; /* expression to infer from, or NULL */
+ Oid infercollid; /* OID of collation, or InvalidOid */
+ Oid inferopfamily; /* OID of att opfamily, or InvalidOid */
+ Oid inferopcinputtype; /* OID of att input type, or InvalidOid */
+} InferenceElem;
+
/*--------------------
* TargetEntry -
* a target entry (used in query target lists)
* single expression tree.
*
* In a SELECT's targetlist, resno should always be equal to the item's
- * ordinal position (counting from 1). However, in an INSERT or UPDATE
+ * ordinal position (counting from 1). However, in an INSERT or UPDATE
* targetlist, resno represents the attribute number of the destination
* column for the item; so there may be missing or out-of-order resnos.
* It is even legal to have duplicated resnos; consider
* UPDATE table SET arraycol[1] = ..., arraycol[2] = ..., ...
* The two meanings come together in the executor, because the planner
* transforms INSERT/UPDATE tlists into a normalized form with exactly
- * one entry for each column of the destination table. Before that's
+ * one entry for each column of the destination table. Before that's
* happened, however, it is risky to assume that resno == position.
* Generally get_tle_by_resno() should be used rather than list_nth()
* to fetch tlist entries by resno, and only in SELECT should you assume
* resname is required to represent the correct column name in non-resjunk
* entries of top-level SELECT targetlists, since it will be used as the
* column title sent to the frontend. In most other contexts it is only
- * a debugging aid, and may be wrong or even NULL. (In particular, it may
+ * a debugging aid, and may be wrong or even NULL. (In particular, it may
* be wrong in a tlist from a stored rule, if the referenced column has been
- * renamed by ALTER TABLE since the rule was made. Also, the planner tends
+ * renamed by ALTER TABLE since the rule was made. Also, the planner tends
* to store NULL rather than look up a valid name for tlist entries in
* non-toplevel plan nodes.) In resjunk entries, resname should be either
* a specific system-generated name (such as "ctid") or NULL; anything else
* risks confusing ExecGetJunkAttribute!
*
- * ressortgroupref is used in the representation of ORDER BY and
- * GROUP BY items. Targetlist entries with ressortgroupref=0 are not
- * sort/group items. If ressortgroupref>0, then this item is an ORDER BY or
- * GROUP BY value. No two entries in a targetlist may have the same nonzero
- * ressortgroupref --- but there is no particular meaning to the nonzero
- * values, except as tags. (For example, one must not assume that lower
- * ressortgroupref means a more significant sort key.) The order of the
- * associated SortClause or GroupClause lists determine the semantics.
+ * ressortgroupref is used in the representation of ORDER BY, GROUP BY, and
+ * DISTINCT items. Targetlist entries with ressortgroupref=0 are not
+ * sort/group items. If ressortgroupref>0, then this item is an ORDER BY,
+ * GROUP BY, and/or DISTINCT target value. No two entries in a targetlist
+ * may have the same nonzero ressortgroupref --- but there is no particular
+ * meaning to the nonzero values, except as tags. (For example, one must
+ * not assume that lower ressortgroupref means a more significant sort key.)
+ * The order of the associated SortGroupClause lists determine the semantics.
*
* resorigtbl/resorigcol identify the source of the column, if it is a
- * simple reference to a column of a base table (or view). If it is not
+ * simple reference to a column of a base table (or view). If it is not
* a simple reference, these fields are zeroes.
*
* If resjunk is true then the column is a working column (such as a sort key)
* or qualified join. Also, FromExpr nodes can appear to denote an
* ordinary cross-product join ("FROM foo, bar, baz WHERE ...").
* FromExpr is like a JoinExpr of jointype JOIN_INNER, except that it
- * may have any number of child nodes, not just two. Also, there is an
- * implementation-defined difference: the planner is allowed to join the
- * children of a FromExpr using whatever join order seems good to it.
- * At present, JoinExpr nodes are always joined in exactly the order
- * implied by the jointree structure (except the planner may choose to
- * swap inner and outer members of a join pair).
+ * may have any number of child nodes, not just two.
*
* NOTE: the top level of a Query's jointree is always a FromExpr.
* Even if the jointree contains no rels, there will be a FromExpr.
*
* NOTE: the qualification expressions present in JoinExpr nodes are
* *in addition to* the query's main WHERE clause, which appears as the
- * qual of the top-level FromExpr. The reason for associating quals with
+ * qual of the top-level FromExpr. The reason for associating quals with
* specific nodes in the jointree is that the position of a qual is critical
* when outer joins are present. (If we enforce a qual too soon or too late,
* that may cause the outer join to produce the wrong set of NULL-extended
/*----------
* JoinExpr - for SQL JOIN expressions
*
- * isNatural, using, and quals are interdependent. The user can write only
- * one of NATURAL, USING(), or ON() (this is enforced by the grammar).
+ * isNatural, usingClause, and quals are interdependent. The user can write
+ * only one of NATURAL, USING(), or ON() (this is enforced by the grammar).
* If he writes NATURAL then parse analysis generates the equivalent USING()
* list, and from that fills in "quals" with the right equality comparisons.
* If he writes USING() then "quals" is filled with equality comparisons.
- * If he writes ON() then only "quals" is set. Note that NATURAL/USING
+ * If he writes ON() then only "quals" is set. Note that NATURAL/USING
* are not equivalent to ON() since they also affect the output column list.
*
* alias is an Alias node representing the AS alias-clause attached to the
* restricts visibility of the tables/columns inside it.
*
* During parse analysis, an RTE is created for the Join, and its index
- * is filled into rtindex. This RTE is present mainly so that Vars can
- * be created that refer to the outputs of the join.
+ * is filled into rtindex. This RTE is present mainly so that Vars can
+ * be created that refer to the outputs of the join. The planner sometimes
+ * generates JoinExprs internally; these can have rtindex = 0 if there are
+ * no join alias variables referencing such joins.
*----------
*/
typedef struct JoinExpr
bool isNatural; /* Natural join? Will need to shape table */
Node *larg; /* left subtree */
Node *rarg; /* right subtree */
- List *using; /* USING clause, if any (list of String) */
+ List *usingClause; /* USING clause, if any (list of String) */
Node *quals; /* qualifiers on join, if any */
Alias *alias; /* user-written alias clause, if any */
- int rtindex; /* RT index assigned for join */
+ int rtindex; /* RT index assigned for join, or 0 */
} JoinExpr;
/*----------
Node *quals; /* qualifiers on join, if any */
} FromExpr;
+/*----------
+ * OnConflictExpr - represents an ON CONFLICT DO ... expression
+ *
+ * The optimizer requires a list of inference elements, and optionally a WHERE
+ * clause to infer a unique index. The unique index (or, occasionally,
+ * indexes) inferred are used to arbitrate whether or not the alternative ON
+ * CONFLICT path is taken.
+ *----------
+ */
+typedef struct OnConflictExpr
+{
+ NodeTag type;
+ OnConflictAction action; /* DO NOTHING or UPDATE? */
+
+ /* Arbiter */
+ List *arbiterElems; /* unique index arbiter list (of InferenceElem's) */
+ Node *arbiterWhere; /* unique index arbiter WHERE clause */
+ Oid constraint; /* pg_constraint OID for arbiter */
+
+ /* ON CONFLICT UPDATE */
+ List *onConflictSet; /* List of ON CONFLICT SET TargetEntrys */
+ Node *onConflictWhere;/* qualifiers to restrict UPDATE to */
+ int exclRelIndex; /* RT index of 'excluded' relation */
+ List *exclRelTlist; /* tlist of the EXCLUDED pseudo relation */
+} OnConflictExpr;
+
#endif /* PRIMNODES_H */
projects / postgresql / blobdiff