* parse_coerce.c
* handle type coercions/conversions for parser
*
- * Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/parser/parse_coerce.c,v 2.98 2003/06/24 23:14:45 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/parser/parse_coerce.c,v 2.136 2006/04/04 19:35:34 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#include "nodes/makefuncs.h"
#include "nodes/params.h"
#include "optimizer/clauses.h"
+#include "parser/parsetree.h"
#include "parser/parse_coerce.h"
#include "parser/parse_expr.h"
#include "parser/parse_func.h"
+#include "parser/parse_relation.h"
#include "parser/parse_type.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
#include "utils/lsyscache.h"
#include "utils/syscache.h"
+#include "utils/typcache.h"
static Node *coerce_type_typmod(Node *node,
- Oid targetTypeId, int32 targetTypMod,
- CoercionForm cformat, bool isExplicit);
-static Node *build_func_call(Oid funcid, Oid rettype, List *args,
- CoercionForm fformat);
+ Oid targetTypeId, int32 targetTypMod,
+ CoercionForm cformat, bool isExplicit,
+ bool hideInputCoercion);
+static void hide_coercion_node(Node *node);
+static Node *build_coercion_expression(Node *node, Oid funcId,
+ Oid targetTypeId, int32 targetTypMod,
+ CoercionForm cformat, bool isExplicit);
+static Node *coerce_record_to_complex(ParseState *pstate, Node *node,
+ Oid targetTypeId,
+ CoercionContext ccontext,
+ CoercionForm cformat);
/*
* Convert an expression to a target type and typmod.
*
* This is the general-purpose entry point for arbitrary type coercion
- * operations. Direct use of the component operations can_coerce_type,
+ * operations. Direct use of the component operations can_coerce_type,
* coerce_type, and coerce_type_typmod should be restricted to special
* cases (eg, when the conversion is expected to succeed).
*
* Returns the possibly-transformed expression tree, or NULL if the type
- * conversion is not possible. (We do this, rather than elog'ing directly,
+ * conversion is not possible. (We do this, rather than ereport'ing directly,
* so that callers can generate custom error messages indicating context.)
*
* pstate - parse state (can be NULL, see coerce_type)
CoercionContext ccontext,
CoercionForm cformat)
{
- if (can_coerce_type(1, &exprtype, &targettype, ccontext))
- expr = coerce_type(pstate, expr, exprtype, targettype,
- ccontext, cformat);
- else if (ccontext >= COERCION_ASSIGNMENT)
- {
- /*
- * String hacks to get transparent conversions for char and varchar:
- * if a coercion to text is available, use it for forced coercions to
- * char(n) or varchar(n) or domains thereof.
- *
- * This is pretty grotty, but seems easier to maintain than providing
- * entries in pg_cast that parallel all the ones for text.
- */
- Oid targetbasetype = getBaseType(targettype);
+ Node *result;
- if (targetbasetype == BPCHAROID || targetbasetype == VARCHAROID)
- {
- Oid text_id = TEXTOID;
+ if (!can_coerce_type(1, &exprtype, &targettype, ccontext))
+ return NULL;
- if (can_coerce_type(1, &exprtype, &text_id, ccontext))
- {
- expr = coerce_type(pstate, expr, exprtype, text_id,
- ccontext, cformat);
- if (targetbasetype != targettype)
- {
- /* need to coerce to domain over char or varchar */
- expr = coerce_to_domain(expr, targetbasetype, targettype,
- cformat);
- }
- else
- {
- /* need a RelabelType if no typmod coercion will be performed */
- if (targettypmod < 0)
- expr = (Node *) makeRelabelType((Expr *) expr,
- targettype, -1,
- cformat);
- }
- }
- else
- expr = NULL;
- }
- else
- expr = NULL;
- }
- else
- expr = NULL;
+ result = coerce_type(pstate, expr, exprtype,
+ targettype, targettypmod,
+ ccontext, cformat);
/*
- * If the target is a fixed-length type, it may need a length coercion
- * as well as a type coercion.
+ * If the target is a fixed-length type, it may need a length coercion as
+ * well as a type coercion. If we find ourselves adding both, force the
+ * inner coercion node to implicit display form.
*/
- if (expr != NULL)
- expr = coerce_type_typmod(expr, targettype, targettypmod,
- cformat,
- (cformat != COERCE_IMPLICIT_CAST));
+ result = coerce_type_typmod(result,
+ targettype, targettypmod,
+ cformat,
+ (cformat != COERCE_IMPLICIT_CAST),
+ (result != expr && !IsA(result, Const)));
- return expr;
+ return result;
}
* The caller should already have determined that the coercion is possible;
* see can_coerce_type.
*
- * No coercion to a typmod (length) is performed here. The caller must
- * call coerce_type_typmod as well, if a typmod constraint is wanted.
+ * Normally, no coercion to a typmod (length) is performed here. The caller
+ * must call coerce_type_typmod as well, if a typmod constraint is wanted.
* (But if the target type is a domain, it may internally contain a
* typmod constraint, which will be applied inside coerce_to_domain.)
+ * In some cases pg_cast specifies a type coercion function that also
+ * applies length conversion, and in those cases only, the result will
+ * already be properly coerced to the specified typmod.
*
* pstate is only used in the case that we are able to resolve the type of
- * a previously UNKNOWN Param. It is okay to pass pstate = NULL if the
+ * a previously UNKNOWN Param. It is okay to pass pstate = NULL if the
* caller does not want type information updated for Params.
*/
Node *
coerce_type(ParseState *pstate, Node *node,
- Oid inputTypeId, Oid targetTypeId,
+ Oid inputTypeId, Oid targetTypeId, int32 targetTypeMod,
CoercionContext ccontext, CoercionForm cformat)
{
Node *result;
/* no conversion needed */
return node;
}
+ if (targetTypeId == ANYOID ||
+ targetTypeId == ANYARRAYOID ||
+ targetTypeId == ANYELEMENTOID)
+ {
+ /* assume can_coerce_type verified that implicit coercion is okay */
+ /* NB: we do NOT want a RelabelType here */
+ return node;
+ }
if (inputTypeId == UNKNOWNOID && IsA(node, Const))
{
/*
- * Input is a string constant with previously undetermined type.
- * Apply the target type's typinput function to it to produce a
- * constant of the target type.
+ * Input is a string constant with previously undetermined type. Apply
+ * the target type's typinput function to it to produce a constant of
+ * the target type.
*
* NOTE: this case cannot be folded together with the other
* constant-input case, since the typinput function does not
* float-to-int type conversion will round to integer.
*
* XXX if the typinput function is not immutable, we really ought to
- * postpone evaluation of the function call until runtime. But
- * there is no way to represent a typinput function call as an
- * expression tree, because C-string values are not Datums. (XXX
- * This *is* possible as of 7.3, do we want to do it?)
+ * postpone evaluation of the function call until runtime. But there
+ * is no way to represent a typinput function call as an expression
+ * tree, because C-string values are not Datums. (XXX This *is*
+ * possible as of 7.3, do we want to do it?)
*/
Const *con = (Const *) node;
Const *newcon = makeNode(Const);
newcon->constbyval = typeByVal(targetType);
newcon->constisnull = con->constisnull;
+ /*
+ * We pass typmod -1 to the input routine, primarily because
+ * existing input routines follow implicit-coercion semantics for
+ * length checks, which is not always what we want here. Any
+ * length constraint will be applied later by our caller.
+ *
+ * We assume here that UNKNOWN's internal representation is the
+ * same as CSTRING.
+ */
if (!con->constisnull)
- {
- char *val = DatumGetCString(DirectFunctionCall1(unknownout,
- con->constvalue));
-
- /*
- * We pass typmod -1 to the input routine, primarily because
- * existing input routines follow implicit-coercion semantics
- * for length checks, which is not always what we want here.
- * Any length constraint will be applied later by our caller.
- *
- * Note that we call stringTypeDatum using the domain's pg_type
- * row, if it's a domain. This works because the domain row has
- * the same typinput and typelem as the base type --- ugly...
- */
- newcon->constvalue = stringTypeDatum(targetType, val, -1);
- pfree(val);
- }
+ newcon->constvalue = stringTypeDatum(targetType,
+ DatumGetCString(con->constvalue),
+ -1);
+ else
+ newcon->constvalue = stringTypeDatum(targetType, NULL, -1);
result = (Node *) newcon;
/* If target is a domain, apply constraints. */
if (targetTyptype == 'd')
result = coerce_to_domain(result, InvalidOid, targetTypeId,
- cformat);
+ cformat, false, false);
ReleaseSysCache(targetType);
pstate != NULL && pstate->p_variableparams)
{
/*
- * Input is a Param of previously undetermined type, and we want
- * to update our knowledge of the Param's type. Find the topmost
+ * Input is a Param of previously undetermined type, and we want to
+ * update our knowledge of the Param's type. Find the topmost
* ParseState and update the state.
*/
Param *param = (Param *) node;
if (paramno <= 0 || /* shouldn't happen, but... */
paramno > toppstate->p_numparams)
- elog(ERROR, "Parameter '$%d' is out of range", paramno);
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_PARAMETER),
+ errmsg("there is no parameter $%d", paramno)));
- if (toppstate->p_paramtypes[paramno-1] == UNKNOWNOID)
+ if (toppstate->p_paramtypes[paramno - 1] == UNKNOWNOID)
{
/* We've successfully resolved the type */
- toppstate->p_paramtypes[paramno-1] = targetTypeId;
+ toppstate->p_paramtypes[paramno - 1] = targetTypeId;
}
- else if (toppstate->p_paramtypes[paramno-1] == targetTypeId)
+ else if (toppstate->p_paramtypes[paramno - 1] == targetTypeId)
{
/* We previously resolved the type, and it matches */
}
else
{
/* Ooops */
- elog(ERROR, "Inconsistent types deduced for parameter '$%d'"
- "\n\tCould be either %s or %s",
- paramno,
- format_type_be(toppstate->p_paramtypes[paramno-1]),
- format_type_be(targetTypeId));
+ ereport(ERROR,
+ (errcode(ERRCODE_AMBIGUOUS_PARAMETER),
+ errmsg("inconsistent types deduced for parameter $%d",
+ paramno),
+ errdetail("%s versus %s",
+ format_type_be(toppstate->p_paramtypes[paramno - 1]),
+ format_type_be(targetTypeId))));
}
param->paramtype = targetTypeId;
- return (Node *) param;
- }
- if (targetTypeId == ANYOID ||
- targetTypeId == ANYARRAYOID ||
- targetTypeId == ANYELEMENTOID)
- {
- /* assume can_coerce_type verified that implicit coercion is okay */
- /* NB: we do NOT want a RelabelType here */
- return node;
+
+ /* Apply domain constraints, if necessary */
+ return coerce_to_domain((Node *) param, InvalidOid, targetTypeId,
+ cformat, false, false);
}
if (find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
&funcId))
if (OidIsValid(funcId))
{
/*
- * Generate an expression tree representing run-time
- * application of the conversion function. If we are dealing
- * with a domain target type, the conversion function will
- * yield the base type.
+ * Generate an expression tree representing run-time application
+ * of the conversion function. If we are dealing with a domain
+ * target type, the conversion function will yield the base type,
+ * and we need to extract the correct typmod to use from the
+ * domain's typtypmod.
*/
Oid baseTypeId = getBaseType(targetTypeId);
+ int32 baseTypeMod;
+
+ if (targetTypeId != baseTypeId)
+ baseTypeMod = get_typtypmod(targetTypeId);
+ else
+ baseTypeMod = targetTypeMod;
- result = build_func_call(funcId, baseTypeId, makeList1(node),
- cformat);
+ result = build_coercion_expression(node, funcId,
+ baseTypeId, baseTypeMod,
+ cformat,
+ (cformat != COERCE_IMPLICIT_CAST));
/*
- * If domain, coerce to the domain type and relabel with
- * domain type ID
+ * If domain, coerce to the domain type and relabel with domain
+ * type ID. We can skip the internal length-coercion step if the
+ * selected coercion function was a type-and-length coercion.
*/
if (targetTypeId != baseTypeId)
result = coerce_to_domain(result, baseTypeId, targetTypeId,
- cformat);
+ cformat, true,
+ exprIsLengthCoercion(result,
+ NULL));
}
else
{
/*
- * We don't need to do a physical conversion, but we do need
- * to attach a RelabelType node so that the expression will be
- * seen to have the intended type when inspected by
- * higher-level code.
+ * We don't need to do a physical conversion, but we do need to
+ * attach a RelabelType node so that the expression will be seen
+ * to have the intended type when inspected by higher-level code.
*
* Also, domains may have value restrictions beyond the base type
- * that must be accounted for. If the destination is a domain
+ * that must be accounted for. If the destination is a domain
* then we won't need a RelabelType node.
*/
result = coerce_to_domain(node, InvalidOid, targetTypeId,
- cformat);
+ cformat, false, false);
if (result == node)
{
/*
}
return result;
}
+ if (inputTypeId == RECORDOID &&
+ ISCOMPLEX(targetTypeId))
+ {
+ /* Coerce a RECORD to a specific complex type */
+ return coerce_record_to_complex(pstate, node, targetTypeId,
+ ccontext, cformat);
+ }
+ if (targetTypeId == RECORDOID &&
+ ISCOMPLEX(inputTypeId))
+ {
+ /* Coerce a specific complex type to RECORD */
+ /* NB: we do NOT want a RelabelType here */
+ return node;
+ }
if (typeInheritsFrom(inputTypeId, targetTypeId))
{
/*
- * Input class type is a subclass of target, so nothing to do ---
- * except relabel the type. This is binary compatibility for
- * complex types.
+ * Input class type is a subclass of target, so generate an
+ * appropriate runtime conversion (removing unneeded columns and
+ * possibly rearranging the ones that are wanted).
*/
- return (Node *) makeRelabelType((Expr *) node,
- targetTypeId, -1,
- cformat);
+ ConvertRowtypeExpr *r = makeNode(ConvertRowtypeExpr);
+
+ r->arg = (Expr *) node;
+ r->resulttype = targetTypeId;
+ r->convertformat = cformat;
+ return (Node *) r;
}
/* If we get here, caller blew it */
- elog(ERROR, "coerce_type: no conversion function from %s to %s",
+ elog(ERROR, "failed to find conversion function from %s to %s",
format_type_be(inputTypeId), format_type_be(targetTypeId));
return NULL; /* keep compiler quiet */
}
if (inputTypeId == targetTypeId)
continue;
- /* don't choke on references to no-longer-existing types */
- if (!typeidIsValid(inputTypeId))
- return false;
- if (!typeidIsValid(targetTypeId))
- return false;
-
- /*
- * If input is an untyped string constant, assume we can convert
- * it to anything except a class type.
- */
- if (inputTypeId == UNKNOWNOID)
- {
- if (ISCOMPLEX(targetTypeId))
- return false;
- continue;
- }
-
/* accept if target is ANY */
if (targetTypeId == ANYOID)
continue;
if (targetTypeId == ANYARRAYOID ||
targetTypeId == ANYELEMENTOID)
{
- have_generics = true; /* do more checking later */
+ have_generics = true; /* do more checking later */
continue;
}
/*
- * If pg_cast shows that we can coerce, accept. This test now
- * covers both binary-compatible and coercion-function cases.
+ * If input is an untyped string constant, assume we can convert it to
+ * anything.
+ */
+ if (inputTypeId == UNKNOWNOID)
+ continue;
+
+ /*
+ * If pg_cast shows that we can coerce, accept. This test now covers
+ * both binary-compatible and coercion-function cases.
*/
if (find_coercion_pathway(targetTypeId, inputTypeId, ccontext,
&funcId))
continue;
+ /*
+ * If input is RECORD and target is a composite type, assume we can
+ * coerce (may need tighter checking here)
+ */
+ if (inputTypeId == RECORDOID &&
+ ISCOMPLEX(targetTypeId))
+ continue;
+
+ /*
+ * If input is a composite type and target is RECORD, accept
+ */
+ if (targetTypeId == RECORDOID &&
+ ISCOMPLEX(inputTypeId))
+ continue;
+
/*
* If input is a class type that inherits from target, accept
*/
* has not bothered to look this up)
* 'typeId': target type to coerce to
* 'cformat': coercion format
+ * 'hideInputCoercion': if true, hide the input coercion under this one.
+ * 'lengthCoercionDone': if true, caller already accounted for length.
*
* If the target type isn't a domain, the given 'arg' is returned as-is.
*/
Node *
-coerce_to_domain(Node *arg, Oid baseTypeId, Oid typeId, CoercionForm cformat)
+coerce_to_domain(Node *arg, Oid baseTypeId, Oid typeId,
+ CoercionForm cformat, bool hideInputCoercion,
+ bool lengthCoercionDone)
{
CoerceToDomain *result;
- int32 typmod;
/* Get the base type if it hasn't been supplied */
if (baseTypeId == InvalidOid)
if (baseTypeId == typeId)
return arg;
+ /* Suppress display of nested coercion steps */
+ if (hideInputCoercion)
+ hide_coercion_node(arg);
+
/*
* If the domain applies a typmod to its base type, build the appropriate
* coercion step. Mark it implicit for display purposes, because we don't
* would be safe to do anyway, without lots of knowledge about what the
* base type thinks the typmod means.
*/
- typmod = get_typtypmod(typeId);
- if (typmod >= 0)
- arg = coerce_type_typmod(arg, baseTypeId, typmod,
- COERCE_IMPLICIT_CAST,
- (cformat != COERCE_IMPLICIT_CAST));
+ if (!lengthCoercionDone)
+ {
+ int32 typmod = get_typtypmod(typeId);
+
+ if (typmod >= 0)
+ arg = coerce_type_typmod(arg, baseTypeId, typmod,
+ COERCE_IMPLICIT_CAST,
+ (cformat != COERCE_IMPLICIT_CAST),
+ false);
+ }
/*
- * Now build the domain coercion node. This represents run-time checking
- * of any constraints currently attached to the domain. This also
- * ensures that the expression is properly labeled as to result type.
+ * Now build the domain coercion node. This represents run-time checking
+ * of any constraints currently attached to the domain. This also ensures
+ * that the expression is properly labeled as to result type.
*/
result = makeNode(CoerceToDomain);
result->arg = (Expr *) arg;
* The caller must have already ensured that the value is of the correct
* type, typically by applying coerce_type.
*
+ * cformat determines the display properties of the generated node (if any),
+ * while isExplicit may affect semantics. If hideInputCoercion is true
+ * *and* we generate a node, the input node is forced to IMPLICIT display
+ * form, so that only the typmod coercion node will be visible when
+ * displaying the expression.
+ *
* NOTE: this does not need to work on domain types, because any typmod
* coercion for a domain is considered to be part of the type coercion
* needed to produce the domain value in the first place. So, no getBaseType.
*/
static Node *
coerce_type_typmod(Node *node, Oid targetTypeId, int32 targetTypMod,
- CoercionForm cformat, bool isExplicit)
+ CoercionForm cformat, bool isExplicit,
+ bool hideInputCoercion)
{
Oid funcId;
- int nargs;
/*
- * A negative typmod is assumed to mean that no coercion is wanted.
+ * A negative typmod is assumed to mean that no coercion is wanted. Also,
+ * skip coercion if already done.
*/
if (targetTypMod < 0 || targetTypMod == exprTypmod(node))
return node;
- funcId = find_typmod_coercion_function(targetTypeId, &nargs);
+ funcId = find_typmod_coercion_function(targetTypeId);
if (OidIsValid(funcId))
{
- List *args;
- Const *cons;
+ /* Suppress display of nested coercion steps */
+ if (hideInputCoercion)
+ hide_coercion_node(node);
+
+ node = build_coercion_expression(node, funcId,
+ targetTypeId, targetTypMod,
+ cformat, isExplicit);
+ }
+
+ return node;
+}
+
+/*
+ * Mark a coercion node as IMPLICIT so it will never be displayed by
+ * ruleutils.c. We use this when we generate a nest of coercion nodes
+ * to implement what is logically one conversion; the inner nodes are
+ * forced to IMPLICIT_CAST format. This does not change their semantics,
+ * only display behavior.
+ *
+ * It is caller error to call this on something that doesn't have a
+ * CoercionForm field.
+ */
+static void
+hide_coercion_node(Node *node)
+{
+ if (IsA(node, FuncExpr))
+ ((FuncExpr *) node)->funcformat = COERCE_IMPLICIT_CAST;
+ else if (IsA(node, RelabelType))
+ ((RelabelType *) node)->relabelformat = COERCE_IMPLICIT_CAST;
+ else if (IsA(node, ConvertRowtypeExpr))
+ ((ConvertRowtypeExpr *) node)->convertformat = COERCE_IMPLICIT_CAST;
+ else if (IsA(node, RowExpr))
+ ((RowExpr *) node)->row_format = COERCE_IMPLICIT_CAST;
+ else if (IsA(node, CoerceToDomain))
+ ((CoerceToDomain *) node)->coercionformat = COERCE_IMPLICIT_CAST;
+ else
+ elog(ERROR, "unsupported node type: %d", (int) nodeTag(node));
+}
+
+/*
+ * build_coercion_expression()
+ * Construct a function-call expression for applying a pg_cast entry.
+ *
+ * This is used for both type-coercion and length-coercion functions,
+ * since there is no difference in terms of the calling convention.
+ */
+static Node *
+build_coercion_expression(Node *node, Oid funcId,
+ Oid targetTypeId, int32 targetTypMod,
+ CoercionForm cformat, bool isExplicit)
+{
+ HeapTuple tp;
+ Form_pg_proc procstruct;
+ int nargs;
+ List *args;
+ Const *cons;
+
+ tp = SearchSysCache(PROCOID,
+ ObjectIdGetDatum(funcId),
+ 0, 0, 0);
+ if (!HeapTupleIsValid(tp))
+ elog(ERROR, "cache lookup failed for function %u", funcId);
+ procstruct = (Form_pg_proc) GETSTRUCT(tp);
+
+ /*
+ * Asserts essentially check that function is a legal coercion function.
+ * We can't make the seemingly obvious tests on prorettype and
+ * proargtypes[0], because of various binary-compatibility cases.
+ */
+ /* Assert(targetTypeId == procstruct->prorettype); */
+ Assert(!procstruct->proretset);
+ Assert(!procstruct->proisagg);
+ nargs = procstruct->pronargs;
+ Assert(nargs >= 1 && nargs <= 3);
+ /* Assert(procstruct->proargtypes.values[0] == exprType(node)); */
+ Assert(nargs < 2 || procstruct->proargtypes.values[1] == INT4OID);
+ Assert(nargs < 3 || procstruct->proargtypes.values[2] == BOOLOID);
- /* Pass given value, plus target typmod as an int4 constant */
+ ReleaseSysCache(tp);
+
+ args = list_make1(node);
+
+ if (nargs >= 2)
+ {
+ /* Pass target typmod as an int4 constant */
cons = makeConst(INT4OID,
sizeof(int32),
Int32GetDatum(targetTypMod),
false,
true);
- args = makeList2(node, cons);
+ args = lappend(args, cons);
+ }
- if (nargs == 3)
- {
- /* Pass it a boolean isExplicit parameter, too */
- cons = makeConst(BOOLOID,
- sizeof(bool),
- BoolGetDatum(isExplicit),
- false,
- true);
-
- args = lappend(args, cons);
- }
+ if (nargs == 3)
+ {
+ /* Pass it a boolean isExplicit parameter, too */
+ cons = makeConst(BOOLOID,
+ sizeof(bool),
+ BoolGetDatum(isExplicit),
+ false,
+ true);
- node = build_func_call(funcId, targetTypeId, args, cformat);
+ args = lappend(args, cons);
}
- return node;
+ return (Node *) makeFuncExpr(funcId, targetTypeId, args, cformat);
}
+/*
+ * coerce_record_to_complex
+ * Coerce a RECORD to a specific composite type.
+ *
+ * Currently we only support this for inputs that are RowExprs or whole-row
+ * Vars.
+ */
+static Node *
+coerce_record_to_complex(ParseState *pstate, Node *node,
+ Oid targetTypeId,
+ CoercionContext ccontext,
+ CoercionForm cformat)
+{
+ RowExpr *rowexpr;
+ TupleDesc tupdesc;
+ List *args = NIL;
+ List *newargs;
+ int i;
+ int ucolno;
+ ListCell *arg;
+
+ if (node && IsA(node, RowExpr))
+ {
+ /*
+ * Since the RowExpr must be of type RECORD, we needn't worry about it
+ * containing any dropped columns.
+ */
+ args = ((RowExpr *) node)->args;
+ }
+ else if (node && IsA(node, Var) &&
+ ((Var *) node)->varattno == InvalidAttrNumber)
+ {
+ int rtindex = ((Var *) node)->varno;
+ int sublevels_up = ((Var *) node)->varlevelsup;
+ RangeTblEntry *rte;
+
+ rte = GetRTEByRangeTablePosn(pstate, rtindex, sublevels_up);
+ expandRTE(rte, rtindex, sublevels_up, false,
+ NULL, &args);
+ }
+ else
+ ereport(ERROR,
+ (errcode(ERRCODE_CANNOT_COERCE),
+ errmsg("cannot cast type %s to %s",
+ format_type_be(RECORDOID),
+ format_type_be(targetTypeId))));
+
+ tupdesc = lookup_rowtype_tupdesc(targetTypeId, -1);
+ newargs = NIL;
+ ucolno = 1;
+ arg = list_head(args);
+ for (i = 0; i < tupdesc->natts; i++)
+ {
+ Node *expr;
+ Oid exprtype;
+
+ /* Fill in NULLs for dropped columns in rowtype */
+ if (tupdesc->attrs[i]->attisdropped)
+ {
+ /*
+ * can't use atttypid here, but it doesn't really matter what type
+ * the Const claims to be.
+ */
+ newargs = lappend(newargs, makeNullConst(INT4OID));
+ continue;
+ }
+
+ if (arg == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_CANNOT_COERCE),
+ errmsg("cannot cast type %s to %s",
+ format_type_be(RECORDOID),
+ format_type_be(targetTypeId)),
+ errdetail("Input has too few columns.")));
+ expr = (Node *) lfirst(arg);
+ exprtype = exprType(expr);
+
+ expr = coerce_to_target_type(pstate,
+ expr, exprtype,
+ tupdesc->attrs[i]->atttypid,
+ tupdesc->attrs[i]->atttypmod,
+ ccontext,
+ COERCE_IMPLICIT_CAST);
+ if (expr == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_CANNOT_COERCE),
+ errmsg("cannot cast type %s to %s",
+ format_type_be(RECORDOID),
+ format_type_be(targetTypeId)),
+ errdetail("Cannot cast type %s to %s in column %d.",
+ format_type_be(exprtype),
+ format_type_be(tupdesc->attrs[i]->atttypid),
+ ucolno)));
+ newargs = lappend(newargs, expr);
+ ucolno++;
+ arg = lnext(arg);
+ }
+ if (arg != NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_CANNOT_COERCE),
+ errmsg("cannot cast type %s to %s",
+ format_type_be(RECORDOID),
+ format_type_be(targetTypeId)),
+ errdetail("Input has too many columns.")));
+
+ rowexpr = makeNode(RowExpr);
+ rowexpr->args = newargs;
+ rowexpr->row_typeid = targetTypeId;
+ rowexpr->row_format = cformat;
+ return (Node *) rowexpr;
+}
+
/* coerce_to_boolean()
* Coerce an argument of a construct that requires boolean input
* (AND, OR, NOT, etc). Also check that input is not a set.
COERCION_ASSIGNMENT,
COERCE_IMPLICIT_CAST);
if (node == NULL)
- {
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
/* translator: first %s is name of a SQL construct, eg WHERE */
- elog(ERROR, "Argument of %s must be type boolean, not type %s",
- constructName, format_type_be(inputTypeId));
- }
+ errmsg("argument of %s must be type boolean, not type %s",
+ constructName, format_type_be(inputTypeId))));
}
if (expression_returns_set(node))
- {
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
/* translator: %s is name of a SQL construct, eg WHERE */
- elog(ERROR, "Argument of %s must not be a set function",
- constructName);
+ errmsg("argument of %s must not return a set",
+ constructName)));
+
+ return node;
+}
+
+/* coerce_to_integer()
+ * Coerce an argument of a construct that requires integer input
+ * (LIMIT, OFFSET, etc). Also check that input is not a set.
+ *
+ * Returns the possibly-transformed node tree.
+ *
+ * As with coerce_type, pstate may be NULL if no special unknown-Param
+ * processing is wanted.
+ */
+Node *
+coerce_to_integer(ParseState *pstate, Node *node,
+ const char *constructName)
+{
+ Oid inputTypeId = exprType(node);
+
+ if (inputTypeId != INT4OID)
+ {
+ node = coerce_to_target_type(pstate, node, inputTypeId,
+ INT4OID, -1,
+ COERCION_ASSIGNMENT,
+ COERCE_IMPLICIT_CAST);
+ if (node == NULL)
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ /* translator: first %s is name of a SQL construct, eg LIMIT */
+ errmsg("argument of %s must be type integer, not type %s",
+ constructName, format_type_be(inputTypeId))));
}
+ if (expression_returns_set(node))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ /* translator: %s is name of a SQL construct, eg LIMIT */
+ errmsg("argument of %s must not return a set",
+ constructName)));
+
return node;
}
{
Oid ptype;
CATEGORY pcategory;
- List *l;
+ ListCell *type_item;
Assert(typeids != NIL);
- ptype = lfirsto(typeids);
+ ptype = getBaseType(linitial_oid(typeids));
pcategory = TypeCategory(ptype);
- foreach(l, lnext(typeids))
+
+ for_each_cell(type_item, lnext(list_head(typeids)))
{
- Oid ntype = lfirsto(l);
+ Oid ntype = getBaseType(lfirst_oid(type_item));
/* move on to next one if no new information... */
if ((ntype != InvalidOid) && (ntype != UNKNOWNOID) && (ntype != ptype))
else if (TypeCategory(ntype) != pcategory)
{
/*
- * both types in different categories? then not much
- * hope...
+ * both types in different categories? then not much hope...
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+
+ /*
+ * translator: first %s is name of a SQL construct, eg CASE
*/
- elog(ERROR, "%s types '%s' and '%s' not matched",
- context, format_type_be(ptype), format_type_be(ntype));
+ errmsg("%s types %s and %s cannot be matched",
+ context,
+ format_type_be(ptype),
+ format_type_be(ntype))));
}
else if (!IsPreferredType(pcategory, ptype) &&
can_coerce_type(1, &ptype, &ntype, COERCION_IMPLICIT) &&
}
/*
- * If all the inputs were UNKNOWN type --- ie, unknown-type literals
- * --- then resolve as type TEXT. This situation comes up with
- * constructs like SELECT (CASE WHEN foo THEN 'bar' ELSE 'baz' END);
- * SELECT 'foo' UNION SELECT 'bar'; It might seem desirable to leave
- * the construct's output type as UNKNOWN, but that really doesn't
- * work, because we'd probably end up needing a runtime coercion from
- * UNKNOWN to something else, and we usually won't have it. We need
- * to coerce the unknown literals while they are still literals, so a
- * decision has to be made now.
+ * If all the inputs were UNKNOWN type --- ie, unknown-type literals ---
+ * then resolve as type TEXT. This situation comes up with constructs
+ * like SELECT (CASE WHEN foo THEN 'bar' ELSE 'baz' END); SELECT 'foo'
+ * UNION SELECT 'bar'; It might seem desirable to leave the construct's
+ * output type as UNKNOWN, but that really doesn't work, because we'd
+ * probably end up needing a runtime coercion from UNKNOWN to something
+ * else, and we usually won't have it. We need to coerce the unknown
+ * literals while they are still literals, so a decision has to be made
+ * now.
*/
if (ptype == UNKNOWNOID)
ptype = TEXTOID;
if (inputTypeId == targetTypeId)
return node; /* no work */
if (can_coerce_type(1, &inputTypeId, &targetTypeId, COERCION_IMPLICIT))
- node = coerce_type(pstate, node, inputTypeId, targetTypeId,
+ node = coerce_type(pstate, node, inputTypeId, targetTypeId, -1,
COERCION_IMPLICIT, COERCE_IMPLICIT_CAST);
else
- elog(ERROR, "%s unable to convert to type %s",
- context, format_type_be(targetTypeId));
+ ereport(ERROR,
+ (errcode(ERRCODE_CANNOT_COERCE),
+ /* translator: first %s is name of a SQL construct, eg CASE */
+ errmsg("%s could not convert type %s to %s",
+ context,
+ format_type_be(inputTypeId),
+ format_type_be(targetTypeId))));
return node;
}
* and must in fact be varlena arrays.
* 2) All arguments declared ANYELEMENT must have matching datatypes.
* 3) If there are arguments of both ANYELEMENT and ANYARRAY, make sure
- * the actual ANYELEMENT datatype is in fact the element type for
- * the actual ANYARRAY datatype.
+ * the actual ANYELEMENT datatype is in fact the element type for
+ * the actual ANYARRAY datatype.
*
* If we have UNKNOWN input (ie, an untyped literal) for any ANYELEMENT
* or ANYARRAY argument, assume it is okay.
*
- * We do not elog here, but just return FALSE if a rule is violated.
+ * If an input is of type ANYARRAY (ie, we know it's an array, but not
+ * what element type), we will accept it as a match to an argument declared
+ * ANYARRAY, so long as we don't have to determine an element type ---
+ * that is, so long as there is no use of ANYELEMENT. This is mostly for
+ * backwards compatibility with the pre-7.4 behavior of ANYARRAY.
+ *
+ * We do not ereport here, but just return FALSE if a rule is violated.
*/
bool
check_generic_type_consistency(Oid *actual_arg_types,
Oid elem_typeid = InvalidOid;
Oid array_typeid = InvalidOid;
Oid array_typelem;
+ bool have_anyelement = false;
/*
- * Loop through the arguments to see if we have any that are
- * ANYARRAY or ANYELEMENT. If so, require the actual types to be
- * self-consistent
+ * Loop through the arguments to see if we have any that are ANYARRAY or
+ * ANYELEMENT. If so, require the actual types to be self-consistent
*/
for (j = 0; j < nargs; j++)
{
- Oid actual_type = actual_arg_types[j];
+ Oid actual_type = actual_arg_types[j];
if (declared_arg_types[j] == ANYELEMENTOID)
{
+ have_anyelement = true;
if (actual_type == UNKNOWNOID)
continue;
if (OidIsValid(elem_typeid) && actual_type != elem_typeid)
/* Get the element type based on the array type, if we have one */
if (OidIsValid(array_typeid))
{
+ if (array_typeid == ANYARRAYOID)
+ {
+ /* Special case for ANYARRAY input: okay iff no ANYELEMENT */
+ if (have_anyelement)
+ return false;
+ return true;
+ }
+
array_typelem = get_element_type(array_typeid);
if (!OidIsValid(array_typelem))
return false; /* should be an array, but isn't */
if (!OidIsValid(elem_typeid))
{
- /* if we don't have an element type yet, use the one we just got */
+ /*
+ * if we don't have an element type yet, use the one we just got
+ */
elem_typeid = array_typelem;
}
else if (array_typelem != elem_typeid)
* if it is declared ANYARRAY or ANYELEMENT:
*
* 1) If return type is ANYARRAY, and any argument is ANYARRAY, use the
- * argument's actual type as the function's return type.
+ * argument's actual type as the function's return type.
* 2) If return type is ANYARRAY, no argument is ANYARRAY, but any argument
- * is ANYELEMENT, use the actual type of the argument to determine
- * the function's return type, i.e. the element type's corresponding
- * array type.
+ * is ANYELEMENT, use the actual type of the argument to determine
+ * the function's return type, i.e. the element type's corresponding
+ * array type.
* 3) If return type is ANYARRAY, no argument is ANYARRAY or ANYELEMENT,
- * generate an ERROR. This condition is prevented by CREATE FUNCTION
- * and is therefore not expected here.
+ * generate an ERROR. This condition is prevented by CREATE FUNCTION
+ * and is therefore not expected here.
* 4) If return type is ANYELEMENT, and any argument is ANYELEMENT, use the
- * argument's actual type as the function's return type.
+ * argument's actual type as the function's return type.
* 5) If return type is ANYELEMENT, no argument is ANYELEMENT, but any
- * argument is ANYARRAY, use the actual type of the argument to determine
- * the function's return type, i.e. the array type's corresponding
- * element type.
+ * argument is ANYARRAY, use the actual type of the argument to determine
+ * the function's return type, i.e. the array type's corresponding
+ * element type.
* 6) If return type is ANYELEMENT, no argument is ANYARRAY or ANYELEMENT,
- * generate an ERROR. This condition is prevented by CREATE FUNCTION
- * and is therefore not expected here.
+ * generate an ERROR. This condition is prevented by CREATE FUNCTION
+ * and is therefore not expected here.
*/
Oid
enforce_generic_type_consistency(Oid *actual_arg_types,
bool have_unknowns = false;
Oid elem_typeid = InvalidOid;
Oid array_typeid = InvalidOid;
- Oid array_typelem = InvalidOid;
+ Oid array_typelem;
+ bool have_anyelement = (rettype == ANYELEMENTOID);
/*
- * Loop through the arguments to see if we have any that are
- * ANYARRAY or ANYELEMENT. If so, require the actual types to be
- * self-consistent
+ * Loop through the arguments to see if we have any that are ANYARRAY or
+ * ANYELEMENT. If so, require the actual types to be self-consistent
*/
for (j = 0; j < nargs; j++)
{
- Oid actual_type = actual_arg_types[j];
+ Oid actual_type = actual_arg_types[j];
if (declared_arg_types[j] == ANYELEMENTOID)
{
- have_generics = true;
+ have_generics = have_anyelement = true;
if (actual_type == UNKNOWNOID)
{
have_unknowns = true;
continue;
}
if (OidIsValid(elem_typeid) && actual_type != elem_typeid)
- elog(ERROR, "Arguments declared ANYELEMENT are not all alike: %s vs %s",
- format_type_be(elem_typeid),
- format_type_be(actual_type));
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("arguments declared \"anyelement\" are not all alike"),
+ errdetail("%s versus %s",
+ format_type_be(elem_typeid),
+ format_type_be(actual_type))));
elem_typeid = actual_type;
}
else if (declared_arg_types[j] == ANYARRAYOID)
continue;
}
if (OidIsValid(array_typeid) && actual_type != array_typeid)
- elog(ERROR, "Arguments declared ANYARRAY are not all alike: %s vs %s",
- format_type_be(array_typeid),
- format_type_be(actual_type));
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("arguments declared \"anyarray\" are not all alike"),
+ errdetail("%s versus %s",
+ format_type_be(array_typeid),
+ format_type_be(actual_type))));
array_typeid = actual_type;
}
}
/*
- * Fast Track: if none of the arguments are ANYARRAY or ANYELEMENT,
- * return the unmodified rettype.
+ * Fast Track: if none of the arguments are ANYARRAY or ANYELEMENT, return
+ * the unmodified rettype.
*/
if (!have_generics)
return rettype;
/* Get the element type based on the array type, if we have one */
if (OidIsValid(array_typeid))
{
- if (array_typeid != ANYARRAYOID)
- array_typelem = get_element_type(array_typeid);
+ if (array_typeid == ANYARRAYOID && !have_anyelement)
+ {
+ /* Special case for ANYARRAY input: okay iff no ANYELEMENT */
+ array_typelem = InvalidOid;
+ }
else
- array_typelem = ANYELEMENTOID;
-
- if (!OidIsValid(array_typelem))
- elog(ERROR, "Argument declared ANYARRAY is not an array: %s",
- format_type_be(array_typeid));
+ {
+ array_typelem = get_element_type(array_typeid);
+ if (!OidIsValid(array_typelem))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("argument declared \"anyarray\" is not an array but type %s",
+ format_type_be(array_typeid))));
+ }
if (!OidIsValid(elem_typeid))
{
- /* if we don't have an element type yet, use the one we just got */
+ /*
+ * if we don't have an element type yet, use the one we just got
+ */
elem_typeid = array_typelem;
}
else if (array_typelem != elem_typeid)
{
/* otherwise, they better match */
- elog(ERROR, "Argument declared ANYARRAY is not consistent with "
- "argument declared ANYELEMENT: %s vs %s",
- format_type_be(array_typeid),
- format_type_be(elem_typeid));
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("argument declared \"anyarray\" is not consistent with argument declared \"anyelement\""),
+ errdetail("%s versus %s",
+ format_type_be(array_typeid),
+ format_type_be(elem_typeid))));
}
}
else if (!OidIsValid(elem_typeid))
{
/* Only way to get here is if all the generic args are UNKNOWN */
- elog(ERROR, "Cannot determine ANYARRAY/ANYELEMENT type because input is UNKNOWN");
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("could not determine anyarray/anyelement type because input has type \"unknown\"")));
}
/*
{
for (j = 0; j < nargs; j++)
{
- Oid actual_type = actual_arg_types[j];
+ Oid actual_type = actual_arg_types[j];
if (actual_type != UNKNOWNOID)
continue;
if (declared_arg_types[j] == ANYELEMENTOID)
- {
declared_arg_types[j] = elem_typeid;
- }
else if (declared_arg_types[j] == ANYARRAYOID)
{
if (!OidIsValid(array_typeid))
{
array_typeid = get_array_type(elem_typeid);
if (!OidIsValid(array_typeid))
- elog(ERROR, "Cannot find array type for datatype %s",
- format_type_be(elem_typeid));
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("could not find array type for data type %s",
+ format_type_be(elem_typeid))));
}
declared_arg_types[j] = array_typeid;
}
{
if (!OidIsValid(array_typeid))
{
- if (elem_typeid != ANYELEMENTOID)
- array_typeid = get_array_type(elem_typeid);
- else
- array_typeid = ANYARRAYOID;
-
+ array_typeid = get_array_type(elem_typeid);
if (!OidIsValid(array_typeid))
- elog(ERROR, "Cannot find array type for datatype %s",
- format_type_be(elem_typeid));
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("could not find array type for data type %s",
+ format_type_be(elem_typeid))));
}
return array_typeid;
}
return rettype;
}
+/*
+ * resolve_generic_type()
+ * Deduce an individual actual datatype on the assumption that
+ * the rules for ANYARRAY/ANYELEMENT are being followed.
+ *
+ * declared_type is the declared datatype we want to resolve.
+ * context_actual_type is the actual input datatype to some argument
+ * that has declared datatype context_declared_type.
+ *
+ * If declared_type isn't polymorphic, we just return it. Otherwise,
+ * context_declared_type must be polymorphic, and we deduce the correct
+ * return type based on the relationship of the two polymorphic types.
+ */
+Oid
+resolve_generic_type(Oid declared_type,
+ Oid context_actual_type,
+ Oid context_declared_type)
+{
+ if (declared_type == ANYARRAYOID)
+ {
+ if (context_declared_type == ANYARRAYOID)
+ {
+ /* Use actual type, but it must be an array */
+ Oid array_typelem = get_element_type(context_actual_type);
+
+ if (!OidIsValid(array_typelem))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("argument declared \"anyarray\" is not an array but type %s",
+ format_type_be(context_actual_type))));
+ return context_actual_type;
+ }
+ else if (context_declared_type == ANYELEMENTOID)
+ {
+ /* Use the array type corresponding to actual type */
+ Oid array_typeid = get_array_type(context_actual_type);
+
+ if (!OidIsValid(array_typeid))
+ ereport(ERROR,
+ (errcode(ERRCODE_UNDEFINED_OBJECT),
+ errmsg("could not find array type for data type %s",
+ format_type_be(context_actual_type))));
+ return array_typeid;
+ }
+ }
+ else if (declared_type == ANYELEMENTOID)
+ {
+ if (context_declared_type == ANYARRAYOID)
+ {
+ /* Use the element type corresponding to actual type */
+ Oid array_typelem = get_element_type(context_actual_type);
+
+ if (!OidIsValid(array_typelem))
+ ereport(ERROR,
+ (errcode(ERRCODE_DATATYPE_MISMATCH),
+ errmsg("argument declared \"anyarray\" is not an array but type %s",
+ format_type_be(context_actual_type))));
+ return array_typelem;
+ }
+ else if (context_declared_type == ANYELEMENTOID)
+ {
+ /* Use the actual type; it doesn't matter if array or not */
+ return context_actual_type;
+ }
+ }
+ else
+ {
+ /* declared_type isn't polymorphic, so return it as-is */
+ return declared_type;
+ }
+ /* If we get here, declared_type is polymorphic and context isn't */
+ /* NB: this is a calling-code logic error, not a user error */
+ elog(ERROR, "could not determine ANYARRAY/ANYELEMENT type because context isn't polymorphic");
+ return InvalidOid; /* keep compiler quiet */
+}
+
/* TypeCategory()
* Assign a category to the specified type OID.
return false;
/*
- * This switch should agree with TypeCategory(), above. Note that
- * at this point, category certainly matches the type.
+ * This switch should agree with TypeCategory(), above. Note that at this
+ * point, category certainly matches the type.
*/
switch (category)
{
break;
default:
- elog(ERROR, "IsPreferredType: unknown category");
+ elog(ERROR, "unrecognized type category: %d", (int) category);
preftype = UNKNOWNOID;
break;
}
* Check if srctype is binary-coercible to targettype.
*
* This notion allows us to cheat and directly exchange values without
- * going through the trouble of calling a conversion function. Note that
- * in general, this should only be an implementation shortcut. Before 7.4,
+ * going through the trouble of calling a conversion function. Note that
+ * in general, this should only be an implementation shortcut. Before 7.4,
* this was also used as a heuristic for resolving overloaded functions and
* operators, but that's basically a bad idea.
*
* invokable, no-function-needed pg_cast entry. Also, a domain is always
* binary-coercible to its base type, though *not* vice versa (in the other
* direction, one must apply domain constraint checks before accepting the
- * value as legitimate).
+ * value as legitimate). We also need to special-case the polymorphic
+ * ANYARRAY type.
*
* This function replaces IsBinaryCompatible(), which was an inherently
- * symmetric test. Since the pg_cast entries aren't necessarily symmetric,
+ * symmetric test. Since the pg_cast entries aren't necessarily symmetric,
* the order of the operands is now significant.
*/
bool
if (srctype == targettype)
return true;
- /* Last of the fast-paths: check for matching polymorphic arrays */
+ /* Also accept any array type as coercible to ANYARRAY */
if (targettype == ANYARRAYOID)
if (get_element_type(srctype) != InvalidOid)
return true;
castcontext = COERCION_EXPLICIT;
break;
default:
- elog(ERROR, "find_coercion_pathway: bogus castcontext %c",
- castForm->castcontext);
+ elog(ERROR, "unrecognized castcontext: %d",
+ (int) castForm->castcontext);
castcontext = 0; /* keep compiler quiet */
break;
}
else
{
/*
- * If there's no pg_cast entry, perhaps we are dealing with a
- * pair of array types. If so, and if the element types have
- * a suitable cast, use array_type_coerce().
+ * If there's no pg_cast entry, perhaps we are dealing with a pair of
+ * array types. If so, and if the element types have a suitable cast,
+ * use array_type_coerce() or array_type_length_coerce().
+ *
+ * Hack: disallow coercions to oidvector and int2vector, which
+ * otherwise tend to capture coercions that should go to "real" array
+ * types. We want those types to be considered "real" arrays for many
+ * purposes, but not this one. (Also, array_type_coerce isn't
+ * guaranteed to produce an output that meets the restrictions of
+ * these datatypes, such as being 1-dimensional.)
*/
Oid targetElemType;
Oid sourceElemType;
Oid elemfuncid;
+ if (targetTypeId == OIDVECTOROID || targetTypeId == INT2VECTOROID)
+ return false;
+
if ((targetElemType = get_element_type(targetTypeId)) != InvalidOid &&
(sourceElemType = get_element_type(sourceTypeId)) != InvalidOid)
{
if (find_coercion_pathway(targetElemType, sourceElemType,
ccontext, &elemfuncid))
{
- *funcid = F_ARRAY_TYPE_COERCE;
+ if (!OidIsValid(elemfuncid))
+ {
+ /* binary-compatible element type conversion */
+ *funcid = F_ARRAY_TYPE_COERCE;
+ }
+ else
+ {
+ /* does the function take a typmod arg? */
+ if (get_func_nargs(elemfuncid) > 1)
+ *funcid = F_ARRAY_TYPE_LENGTH_COERCE;
+ else
+ *funcid = F_ARRAY_TYPE_COERCE;
+ }
result = true;
}
}
/*
* find_typmod_coercion_function -- does the given type need length coercion?
*
- * If the target type possesses a function named for the type
- * and having parameter signature (targettype, int4), we assume that
- * the type requires coercion to its own length and that the said
- * function should be invoked to do that.
- *
- * Alternatively, the length-coercing function may have the signature
- * (targettype, int4, bool). On success, *nargs is set to report which
- * signature we found.
+ * If the target type possesses a pg_cast function from itself to itself,
+ * it must need length coercion.
*
* "bpchar" (ie, char(N)) and "numeric" are examples of such types.
*
* function associated directly with the array type, but instead look for
* one associated with the element type. If one exists, we report
* array_length_coerce() as the coercion function to use.
- *
- * This mechanism may seem pretty grotty and in need of replacement by
- * something in pg_cast, but since typmod is only interesting for datatypes
- * that have special handling in the grammar, there's not really much
- * percentage in making it any easier to apply such coercions ...
*/
Oid
-find_typmod_coercion_function(Oid typeId, int *nargs)
+find_typmod_coercion_function(Oid typeId)
{
Oid funcid = InvalidOid;
bool isArray = false;
Type targetType;
Form_pg_type typeForm;
- char *typname;
- Oid typnamespace;
- Oid oid_array[FUNC_MAX_ARGS];
- HeapTuple ftup;
+ HeapTuple tuple;
targetType = typeidType(typeId);
typeForm = (Form_pg_type) GETSTRUCT(targetType);
{
/* Yes, switch our attention to the element type */
typeId = typeForm->typelem;
- ReleaseSysCache(targetType);
- targetType = typeidType(typeId);
- typeForm = (Form_pg_type) GETSTRUCT(targetType);
isArray = true;
}
+ ReleaseSysCache(targetType);
- /* Function name is same as type internal name, and in same namespace */
- typname = NameStr(typeForm->typname);
- typnamespace = typeForm->typnamespace;
-
- /* First look for parameters (type, int4) */
- MemSet(oid_array, 0, FUNC_MAX_ARGS * sizeof(Oid));
- oid_array[0] = typeId;
- oid_array[1] = INT4OID;
- *nargs = 2;
-
- ftup = SearchSysCache(PROCNAMENSP,
- CStringGetDatum(typname),
- Int16GetDatum(2),
- PointerGetDatum(oid_array),
- ObjectIdGetDatum(typnamespace));
- if (HeapTupleIsValid(ftup))
- {
- Form_pg_proc pform = (Form_pg_proc) GETSTRUCT(ftup);
-
- /* Make sure the function's result type is as expected */
- if (pform->prorettype == typeId && !pform->proretset &&
- !pform->proisagg)
- {
- /* Okay to use it */
- funcid = HeapTupleGetOid(ftup);
- }
- ReleaseSysCache(ftup);
- }
+ /* Look in pg_cast */
+ tuple = SearchSysCache(CASTSOURCETARGET,
+ ObjectIdGetDatum(typeId),
+ ObjectIdGetDatum(typeId),
+ 0, 0);
- if (!OidIsValid(funcid))
+ if (HeapTupleIsValid(tuple))
{
- /* Didn't find a function, so now try (type, int4, bool) */
- oid_array[2] = BOOLOID;
- *nargs = 3;
-
- ftup = SearchSysCache(PROCNAMENSP,
- CStringGetDatum(typname),
- Int16GetDatum(3),
- PointerGetDatum(oid_array),
- ObjectIdGetDatum(typnamespace));
- if (HeapTupleIsValid(ftup))
- {
- Form_pg_proc pform = (Form_pg_proc) GETSTRUCT(ftup);
+ Form_pg_cast castForm = (Form_pg_cast) GETSTRUCT(tuple);
- /* Make sure the function's result type is as expected */
- if (pform->prorettype == typeId && !pform->proretset &&
- !pform->proisagg)
- {
- /* Okay to use it */
- funcid = HeapTupleGetOid(ftup);
- }
- ReleaseSysCache(ftup);
- }
+ funcid = castForm->castfunc;
+ ReleaseSysCache(tuple);
}
- ReleaseSysCache(targetType);
-
/*
* Now, if we did find a coercion function for an array element type,
- * report array_length_coerce() as the function to use. We know it
- * takes three arguments always.
+ * report array_length_coerce() as the function to use.
*/
if (isArray && OidIsValid(funcid))
- {
funcid = F_ARRAY_LENGTH_COERCE;
- *nargs = 3;
- }
return funcid;
}
-
-/*
- * Build an expression tree representing a function call.
- *
- * The argument expressions must have been transformed already.
- */
-static Node *
-build_func_call(Oid funcid, Oid rettype, List *args, CoercionForm fformat)
-{
- FuncExpr *funcexpr;
-
- funcexpr = makeNode(FuncExpr);
- funcexpr->funcid = funcid;
- funcexpr->funcresulttype = rettype;
- funcexpr->funcretset = false; /* only possible case here */
- funcexpr->funcformat = fformat;
- funcexpr->args = args;
-
- return (Node *) funcexpr;
-}