-/* ----------
+/*-------------------------------------------------------------------------
+ *
* ri_triggers.c
*
* Generic trigger procedures for referential integrity constraint
*
* src/backend/utils/adt/ri_triggers.c
*
- * ----------
+ *-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "utils/syscache.h"
-/* ----------
+/*
* Local definitions
- * ----------
*/
#define RI_MAX_NUMKEYS INDEX_MAX_KEYS
#define RI_TRIGTYPE_DELETE 3
-/* ----------
+/*
* RI_ConstraintInfo
*
- * Information extracted from an FK pg_constraint entry. This is cached in
- * ri_constraint_cache.
- * ----------
+ * Information extracted from an FK pg_constraint entry. This is cached in
+ * ri_constraint_cache.
*/
typedef struct RI_ConstraintInfo
{
dlist_node valid_link; /* Link in list of valid entries */
} RI_ConstraintInfo;
-
-/* ----------
+/*
* RI_QueryKey
*
- * The key identifying a prepared SPI plan in our query hashtable
- * ----------
+ * The key identifying a prepared SPI plan in our query hashtable
*/
typedef struct RI_QueryKey
{
int32 constr_queryno; /* query type ID, see RI_PLAN_XXX above */
} RI_QueryKey;
-
-/* ----------
+/*
* RI_QueryHashEntry
- * ----------
*/
typedef struct RI_QueryHashEntry
{
SPIPlanPtr plan;
} RI_QueryHashEntry;
-
-/* ----------
+/*
* RI_CompareKey
*
- * The key identifying an entry showing how to compare two values
- * ----------
+ * The key identifying an entry showing how to compare two values
*/
typedef struct RI_CompareKey
{
Oid typeid; /* the data type to apply it to */
} RI_CompareKey;
-
-/* ----------
+/*
* RI_CompareHashEntry
- * ----------
*/
typedef struct RI_CompareHashEntry
{
} RI_CompareHashEntry;
-/* ----------
+/*
* Local data
- * ----------
*/
static HTAB *ri_constraint_cache = NULL;
static HTAB *ri_query_cache = NULL;
static int ri_constraint_cache_valid_count = 0;
-/* ----------
+/*
* Local function prototypes
- * ----------
*/
static bool ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
TupleTableSlot *oldslot,
int queryno) pg_attribute_noreturn();
-/* ----------
+/*
* RI_FKey_check -
*
- * Check foreign key existence (combined for INSERT and UPDATE).
- * ----------
+ * Check foreign key existence (combined for INSERT and UPDATE).
*/
static Datum
RI_FKey_check(TriggerData *trigdata)
SPIPlanPtr qplan;
int i;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, false);
if (SPI_connect() != SPI_OK_CONNECT)
elog(ERROR, "SPI_connect failed");
- /*
- * Fetch or prepare a saved plan for the real check
- */
+ /* Fetch or prepare a saved plan for the real check */
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CHECK_LOOKUPPK);
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
}
-/* ----------
+/*
* RI_FKey_check_ins -
*
- * Check foreign key existence at insert event on FK table.
- * ----------
+ * Check foreign key existence at insert event on FK table.
*/
Datum
RI_FKey_check_ins(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_check_ins", RI_TRIGTYPE_INSERT);
- /*
- * Share code with UPDATE case.
- */
+ /* Share code with UPDATE case. */
return RI_FKey_check((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* RI_FKey_check_upd -
*
- * Check foreign key existence at update event on FK table.
- * ----------
+ * Check foreign key existence at update event on FK table.
*/
Datum
RI_FKey_check_upd(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_check_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Share code with INSERT case.
- */
+ /* Share code with INSERT case. */
return RI_FKey_check((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* ri_Check_Pk_Match
*
* Check to see if another PK row has been created that provides the same
*
* We assume the caller checked that the old_row contains no NULL key values,
* since otherwise a match is impossible.
- * ----------
*/
static bool
ri_Check_Pk_Match(Relation pk_rel, Relation fk_rel,
}
-/* ----------
+/*
* RI_FKey_noaction_del -
*
- * Give an error and roll back the current transaction if the
- * delete has resulted in a violation of the given referential
- * integrity constraint.
- * ----------
+ * Give an error and roll back the current transaction if the
+ * delete has resulted in a violation of the given referential
+ * integrity constraint.
*/
Datum
RI_FKey_noaction_del(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_noaction_del", RI_TRIGTYPE_DELETE);
- /*
- * Share code with RESTRICT/UPDATE cases.
- */
+ /* Share code with RESTRICT/UPDATE cases. */
return ri_restrict((TriggerData *) fcinfo->context, true);
}
-/* ----------
+/*
* RI_FKey_restrict_del -
*
- * Restrict delete from PK table to rows unreferenced by foreign key.
+ * Restrict delete from PK table to rows unreferenced by foreign key.
*
- * The SQL standard intends that this referential action occur exactly when
- * the delete is performed, rather than after. This appears to be
- * the only difference between "NO ACTION" and "RESTRICT". In Postgres
- * we still implement this as an AFTER trigger, but it's non-deferrable.
- * ----------
+ * The SQL standard intends that this referential action occur exactly when
+ * the delete is performed, rather than after. This appears to be
+ * the only difference between "NO ACTION" and "RESTRICT". In Postgres
+ * we still implement this as an AFTER trigger, but it's non-deferrable.
*/
Datum
RI_FKey_restrict_del(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_restrict_del", RI_TRIGTYPE_DELETE);
- /*
- * Share code with NO ACTION/UPDATE cases.
- */
+ /* Share code with NO ACTION/UPDATE cases. */
return ri_restrict((TriggerData *) fcinfo->context, false);
}
-/* ----------
+/*
* RI_FKey_noaction_upd -
*
- * Give an error and roll back the current transaction if the
- * update has resulted in a violation of the given referential
- * integrity constraint.
- * ----------
+ * Give an error and roll back the current transaction if the
+ * update has resulted in a violation of the given referential
+ * integrity constraint.
*/
Datum
RI_FKey_noaction_upd(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_noaction_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Share code with RESTRICT/DELETE cases.
- */
+ /* Share code with RESTRICT/DELETE cases. */
return ri_restrict((TriggerData *) fcinfo->context, true);
}
-/* ----------
+/*
* RI_FKey_restrict_upd -
*
- * Restrict update of PK to rows unreferenced by foreign key.
+ * Restrict update of PK to rows unreferenced by foreign key.
*
- * The SQL standard intends that this referential action occur exactly when
- * the update is performed, rather than after. This appears to be
- * the only difference between "NO ACTION" and "RESTRICT". In Postgres
- * we still implement this as an AFTER trigger, but it's non-deferrable.
- * ----------
+ * The SQL standard intends that this referential action occur exactly when
+ * the update is performed, rather than after. This appears to be
+ * the only difference between "NO ACTION" and "RESTRICT". In Postgres
+ * we still implement this as an AFTER trigger, but it's non-deferrable.
*/
Datum
RI_FKey_restrict_upd(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_restrict_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Share code with NO ACTION/DELETE cases.
- */
+ /* Share code with NO ACTION/DELETE cases. */
return ri_restrict((TriggerData *) fcinfo->context, false);
}
-/* ----------
+/*
* ri_restrict -
*
- * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
- * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
- * ----------
+ * Common code for ON DELETE RESTRICT, ON DELETE NO ACTION,
+ * ON UPDATE RESTRICT, and ON UPDATE NO ACTION.
*/
static Datum
ri_restrict(TriggerData *trigdata, bool is_no_action)
RI_QueryKey qkey;
SPIPlanPtr qplan;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, true);
}
-/* ----------
+/*
* RI_FKey_cascade_del -
*
- * Cascaded delete foreign key references at delete event on PK table.
- * ----------
+ * Cascaded delete foreign key references at delete event on PK table.
*/
Datum
RI_FKey_cascade_del(PG_FUNCTION_ARGS)
SPIPlanPtr qplan;
int i;
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_cascade_del", RI_TRIGTYPE_DELETE);
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, true);
if (SPI_connect() != SPI_OK_CONNECT)
elog(ERROR, "SPI_connect failed");
- /*
- * Fetch or prepare a saved plan for the cascaded delete
- */
+ /* Fetch or prepare a saved plan for the cascaded delete */
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_DEL_DODELETE);
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
}
-/* ----------
+/*
* RI_FKey_cascade_upd -
*
- * Cascaded update foreign key references at update event on PK table.
- * ----------
+ * Cascaded update foreign key references at update event on PK table.
*/
Datum
RI_FKey_cascade_upd(PG_FUNCTION_ARGS)
int i;
int j;
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_cascade_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, true);
if (SPI_connect() != SPI_OK_CONNECT)
elog(ERROR, "SPI_connect failed");
- /*
- * Fetch or prepare a saved plan for the cascaded update
- */
+ /* Fetch or prepare a saved plan for the cascaded update */
ri_BuildQueryKey(&qkey, riinfo, RI_PLAN_CASCADE_UPD_DOUPDATE);
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
}
-/* ----------
+/*
* RI_FKey_setnull_del -
*
- * Set foreign key references to NULL values at delete event on PK table.
- * ----------
+ * Set foreign key references to NULL values at delete event on PK table.
*/
Datum
RI_FKey_setnull_del(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_setnull_del", RI_TRIGTYPE_DELETE);
- /*
- * Share code with UPDATE case
- */
+ /* Share code with UPDATE case */
return ri_setnull((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* RI_FKey_setnull_upd -
*
- * Set foreign key references to NULL at update event on PK table.
- * ----------
+ * Set foreign key references to NULL at update event on PK table.
*/
Datum
RI_FKey_setnull_upd(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_setnull_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Share code with DELETE case
- */
+ /* Share code with DELETE case */
return ri_setnull((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* ri_setnull -
*
- * Common code for ON DELETE SET NULL and ON UPDATE SET NULL
- * ----------
+ * Common code for ON DELETE SET NULL and ON UPDATE SET NULL
*/
static Datum
ri_setnull(TriggerData *trigdata)
SPIPlanPtr qplan;
int i;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, true);
}
-/* ----------
+/*
* RI_FKey_setdefault_del -
*
- * Set foreign key references to defaults at delete event on PK table.
- * ----------
+ * Set foreign key references to defaults at delete event on PK table.
*/
Datum
RI_FKey_setdefault_del(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_del", RI_TRIGTYPE_DELETE);
- /*
- * Share code with UPDATE case
- */
+ /* Share code with UPDATE case */
return ri_setdefault((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* RI_FKey_setdefault_upd -
*
- * Set foreign key references to defaults at update event on PK table.
- * ----------
+ * Set foreign key references to defaults at update event on PK table.
*/
Datum
RI_FKey_setdefault_upd(PG_FUNCTION_ARGS)
{
- /*
- * Check that this is a valid trigger call on the right time and event.
- */
+ /* Check that this is a valid trigger call on the right time and event. */
ri_CheckTrigger(fcinfo, "RI_FKey_setdefault_upd", RI_TRIGTYPE_UPDATE);
- /*
- * Share code with DELETE case
- */
+ /* Share code with DELETE case */
return ri_setdefault((TriggerData *) fcinfo->context);
}
-/* ----------
+/*
* ri_setdefault -
*
- * Common code for ON DELETE SET DEFAULT and ON UPDATE SET DEFAULT
- * ----------
+ * Common code for ON DELETE SET DEFAULT and ON UPDATE SET DEFAULT
*/
static Datum
ri_setdefault(TriggerData *trigdata)
RI_QueryKey qkey;
SPIPlanPtr qplan;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigdata->tg_trigger,
trigdata->tg_relation, true);
}
-/* ----------
+/*
* RI_FKey_pk_upd_check_required -
*
- * Check if we really need to fire the RI trigger for an update or delete to a PK
- * relation. This is called by the AFTER trigger queue manager to see if
- * it can skip queuing an instance of an RI trigger. Returns true if the
- * trigger must be fired, false if we can prove the constraint will still
- * be satisfied.
+ * Check if we really need to fire the RI trigger for an update or delete to a PK
+ * relation. This is called by the AFTER trigger queue manager to see if
+ * it can skip queuing an instance of an RI trigger. Returns true if the
+ * trigger must be fired, false if we can prove the constraint will still
+ * be satisfied.
*
- * new_slot will be NULL if this is called for a delete.
- * ----------
+ * new_slot will be NULL if this is called for a delete.
*/
bool
RI_FKey_pk_upd_check_required(Trigger *trigger, Relation pk_rel,
{
const RI_ConstraintInfo *riinfo;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigger, pk_rel, true);
/*
return true;
}
-/* ----------
+/*
* RI_FKey_fk_upd_check_required -
*
- * Check if we really need to fire the RI trigger for an update to an FK
- * relation. This is called by the AFTER trigger queue manager to see if
- * it can skip queuing an instance of an RI trigger. Returns true if the
- * trigger must be fired, false if we can prove the constraint will still
- * be satisfied.
- * ----------
+ * Check if we really need to fire the RI trigger for an update to an FK
+ * relation. This is called by the AFTER trigger queue manager to see if
+ * it can skip queuing an instance of an RI trigger. Returns true if the
+ * trigger must be fired, false if we can prove the constraint will still
+ * be satisfied.
*/
bool
RI_FKey_fk_upd_check_required(Trigger *trigger, Relation fk_rel,
TransactionId xmin;
bool isnull;
- /*
- * Get arguments.
- */
riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
ri_nullcheck = ri_NullCheck(RelationGetDescr(fk_rel), new_slot, riinfo, false);
return true;
}
-/* ----------
+/*
* RI_Initial_Check -
*
- * Check an entire table for non-matching values using a single query.
- * This is not a trigger procedure, but is called during ALTER TABLE
- * ADD FOREIGN KEY to validate the initial table contents.
+ * Check an entire table for non-matching values using a single query.
+ * This is not a trigger procedure, but is called during ALTER TABLE
+ * ADD FOREIGN KEY to validate the initial table contents.
*
- * We expect that the caller has made provision to prevent any problems
- * caused by concurrent actions. This could be either by locking rel and
- * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
- * that triggers implementing the checks are already active.
- * Hence, we do not need to lock individual rows for the check.
+ * We expect that the caller has made provision to prevent any problems
+ * caused by concurrent actions. This could be either by locking rel and
+ * pkrel at ShareRowExclusiveLock or higher, or by otherwise ensuring
+ * that triggers implementing the checks are already active.
+ * Hence, we do not need to lock individual rows for the check.
*
- * If the check fails because the current user doesn't have permissions
- * to read both tables, return false to let our caller know that they will
- * need to do something else to check the constraint.
- * ----------
+ * If the check fails because the current user doesn't have permissions
+ * to read both tables, return false to let our caller know that they will
+ * need to do something else to check the constraint.
*/
bool
RI_Initial_Check(Trigger *trigger, Relation fk_rel, Relation pk_rel)
int spi_result;
SPIPlanPtr qplan;
- /* Fetch constraint info. */
riinfo = ri_FetchConstraintInfo(trigger, fk_rel, false);
/*
}
-/* ----------
+/*
* ri_NullCheck -
*
- * Determine the NULL state of all key values in a tuple
+ * Determine the NULL state of all key values in a tuple
*
- * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
- * ----------
+ * Returns one of RI_KEYS_ALL_NULL, RI_KEYS_NONE_NULL or RI_KEYS_SOME_NULL.
*/
static int
ri_NullCheck(TupleDesc tupDesc,
}
-/* ----------
+/*
* ri_InitHashTables -
*
- * Initialize our internal hash tables.
- * ----------
+ * Initialize our internal hash tables.
*/
static void
ri_InitHashTables(void)
}
-/* ----------
+/*
* ri_FetchPreparedPlan -
*
- * Lookup for a query key in our private hash table of prepared
- * and saved SPI execution plans. Return the plan if found or NULL.
- * ----------
+ * Lookup for a query key in our private hash table of prepared
+ * and saved SPI execution plans. Return the plan if found or NULL.
*/
static SPIPlanPtr
ri_FetchPreparedPlan(RI_QueryKey *key)
}
-/* ----------
+/*
* ri_HashPreparedPlan -
*
- * Add another plan to our private SPI query plan hashtable.
- * ----------
+ * Add another plan to our private SPI query plan hashtable.
*/
static void
ri_HashPreparedPlan(RI_QueryKey *key, SPIPlanPtr plan)
}
-/* ----------
+/*
* ri_KeysEqual -
*
- * Check if all key values in OLD and NEW are equal.
+ * Check if all key values in OLD and NEW are equal.
*
- * Note: at some point we might wish to redefine this as checking for
- * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
- * considered equal. Currently there is no need since all callers have
- * previously found at least one of the rows to contain no nulls.
- * ----------
+ * Note: at some point we might wish to redefine this as checking for
+ * "IS NOT DISTINCT" rather than "=", that is, allow two nulls to be
+ * considered equal. Currently there is no need since all callers have
+ * previously found at least one of the rows to contain no nulls.
*/
static bool
ri_KeysEqual(Relation rel, TupleTableSlot *oldslot, TupleTableSlot *newslot,
}
-/* ----------
+/*
* ri_AttributesEqual -
*
- * Call the appropriate equality comparison operator for two values.
+ * Call the appropriate equality comparison operator for two values.
*
- * NB: we have already checked that neither value is null.
- * ----------
+ * NB: we have already checked that neither value is null.
*/
static bool
ri_AttributesEqual(Oid eq_opr, Oid typeid,
oldvalue, newvalue));
}
-/* ----------
+/*
* ri_HashCompareOp -
*
- * See if we know how to compare two values, and create a new hash entry
- * if not.
- * ----------
+ * See if we know how to compare two values, and create a new hash entry
+ * if not.
*/
static RI_CompareHashEntry *
ri_HashCompareOp(Oid eq_opr, Oid typeid)
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