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Diffstat (limited to 'src/backend/access/table/table.c')
| -rw-r--r-- | src/backend/access/table/table.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/src/backend/access/table/table.c b/src/backend/access/table/table.c new file mode 100644 index 0000000..744d3b5 --- /dev/null +++ b/src/backend/access/table/table.c @@ -0,0 +1,170 @@ +/*------------------------------------------------------------------------- + * + * table.c + * Generic routines for table related code. + * + * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/backend/access/table/table.c + * + * + * NOTES + * This file contains table_ routines that implement access to tables (in + * contrast to other relation types like indexes) that are independent of + * individual table access methods. + * + *------------------------------------------------------------------------- + */ + +#include "postgres.h" + +#include "access/relation.h" +#include "access/table.h" +#include "storage/lmgr.h" + + +/* ---------------- + * table_open - open a table relation by relation OID + * + * This is essentially relation_open plus check that the relation + * is not an index nor a composite type. (The caller should also + * check that it's not a view or foreign table before assuming it has + * storage.) + * ---------------- + */ +Relation +table_open(Oid relationId, LOCKMODE lockmode) +{ + Relation r; + + r = relation_open(relationId, lockmode); + + if (r->rd_rel->relkind == RELKIND_INDEX || + r->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an index", + RelationGetRelationName(r)))); + else if (r->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is a composite type", + RelationGetRelationName(r)))); + + return r; +} + + +/* ---------------- + * try_table_open - open a table relation by relation OID + * + * Same as table_open, except return NULL instead of failing + * if the relation does not exist. + * ---------------- + */ +Relation +try_table_open(Oid relationId, LOCKMODE lockmode) +{ + Relation r; + + r = try_relation_open(relationId, lockmode); + + /* leave if table does not exist */ + if (!r) + return NULL; + + if (r->rd_rel->relkind == RELKIND_INDEX || + r->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an index", + RelationGetRelationName(r)))); + else if (r->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is a composite type", + RelationGetRelationName(r)))); + + return r; +} + +/* ---------------- + * table_openrv - open a table relation specified + * by a RangeVar node + * + * As above, but relation is specified by a RangeVar. + * ---------------- + */ +Relation +table_openrv(const RangeVar *relation, LOCKMODE lockmode) +{ + Relation r; + + r = relation_openrv(relation, lockmode); + + if (r->rd_rel->relkind == RELKIND_INDEX || + r->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an index", + RelationGetRelationName(r)))); + else if (r->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is a composite type", + RelationGetRelationName(r)))); + + return r; +} + +/* ---------------- + * table_openrv_extended - open a table relation specified + * by a RangeVar node + * + * As above, but optionally return NULL instead of failing for + * relation-not-found. + * ---------------- + */ +Relation +table_openrv_extended(const RangeVar *relation, LOCKMODE lockmode, + bool missing_ok) +{ + Relation r; + + r = relation_openrv_extended(relation, lockmode, missing_ok); + + if (r) + { + if (r->rd_rel->relkind == RELKIND_INDEX || + r->rd_rel->relkind == RELKIND_PARTITIONED_INDEX) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an index", + RelationGetRelationName(r)))); + else if (r->rd_rel->relkind == RELKIND_COMPOSITE_TYPE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is a composite type", + RelationGetRelationName(r)))); + } + + return r; +} + +/* ---------------- + * table_close - close a table + * + * If lockmode is not "NoLock", we then release the specified lock. + * + * Note that it is often sensible to hold a lock beyond relation_close; + * in that case, the lock is released automatically at xact end. + * ---------------- + */ +void +table_close(Relation relation, LOCKMODE lockmode) +{ + relation_close(relation, lockmode); +} |