gram.y

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

 *****************************************************************************/

ClosePortalStmt:
			CLOSE name
				{
					ClosePortalStmt *n = makeNode(ClosePortalStmt);
					n->portalname = $2;
					$$ = (Node *)n;
				}
		;


/*****************************************************************************
 *
 *		QUERY :
 *				COPY <relname> ['(' columnList ')'] FROM/TO [WITH options]
 *
 *				BINARY, OIDS, and DELIMITERS kept in old locations
 *				for backward compatibility.  2002-06-18
 *
 *****************************************************************************/

CopyStmt:	COPY opt_binary qualified_name opt_column_list opt_oids
			copy_from copy_file_name copy_delimiter opt_with copy_opt_list
				{
					CopyStmt *n = makeNode(CopyStmt);
					n->relation = $3;
					n->attlist = $4;
					n->is_from = $6;
					n->filename = $7;

					n->options = NIL;
					/* Concatenate user-supplied flags */
					if ($2)
						n->options = lappend(n->options, $2);
					if ($5)
						n->options = lappend(n->options, $5);
					if ($8)
						n->options = lappend(n->options, $8);
					if ($10)
						n->options = list_concat(n->options, $10);
					$$ = (Node *)n;
				}
		;

copy_from:
			FROM									{ $$ = TRUE; }
			| TO									{ $$ = FALSE; }
		;

/*
 * copy_file_name NULL indicates stdio is used. Whether stdin or stdout is
 * used depends on the direction. (It really doesn't make sense to copy from
 * stdout. We silently correct the "typo".		 - AY 9/94
 */
copy_file_name:
			Sconst									{ $$ = $1; }
			| STDIN									{ $$ = NULL; }
			| STDOUT								{ $$ = NULL; }
		;



copy_opt_list:
			copy_opt_list copy_opt_item				{ $$ = lappend($1, $2); }
			| /* EMPTY */							{ $$ = NIL; }
		;


copy_opt_item:
			BINARY
				{
					$$ = makeDefElem("binary", (Node *)makeInteger(TRUE));
				}
			| OIDS
				{
					$$ = makeDefElem("oids", (Node *)makeInteger(TRUE));
				}
			| DELIMITER opt_as Sconst
				{
					$$ = makeDefElem("delimiter", (Node *)makeString($3));
				}
			| NULL_P opt_as Sconst
				{
					$$ = makeDefElem("null", (Node *)makeString($3));
				}
			| CSV
				{
					$$ = makeDefElem("csv", (Node *)makeInteger(TRUE));
				}
			| HEADER
				{
					$$ = makeDefElem("header", (Node *)makeInteger(TRUE));
				}
			| QUOTE opt_as Sconst
				{
					$$ = makeDefElem("quote", (Node *)makeString($3));
				}
			| ESCAPE opt_as Sconst
				{
					$$ = makeDefElem("escape", (Node *)makeString($3));
				}
			| FORCE QUOTE columnList
				{
					$$ = makeDefElem("force_quote", (Node *)$3);
				}
			| FORCE NOT NULL_P columnList
				{
					$$ = makeDefElem("force_notnull", (Node *)$4);
				}
		;

/* The following exist for backward compatibility */

opt_binary:
			BINARY
				{
					$$ = makeDefElem("binary", (Node *)makeInteger(TRUE));
				}
			| /*EMPTY*/								{ $$ = NULL; }
		;

opt_oids:
			WITH OIDS
				{
					$$ = makeDefElem("oids", (Node *)makeInteger(TRUE));
				}
			| /*EMPTY*/								{ $$ = NULL; }
		;

copy_delimiter:
			/* USING DELIMITERS kept for backward compatibility. 2002-06-15 */
			opt_using DELIMITERS Sconst
				{
					$$ = makeDefElem("delimiter", (Node *)makeString($3));
				}
			| /*EMPTY*/								{ $$ = NULL; }
		;

opt_using:
			USING									{}
			| /*EMPTY*/								{}
		;


/*****************************************************************************
 *
 *		QUERY :
 *				CREATE TABLE relname
 *
 *****************************************************************************/

CreateStmt:	CREATE OptTemp TABLE qualified_name '(' OptTableElementList ')'
			OptInherit OptWithOids OnCommitOption OptTableSpace
				{
					CreateStmt *n = makeNode(CreateStmt);
					$4->istemp = $2;
					n->relation = $4;
					n->tableElts = $6;
					n->inhRelations = $8;
					n->constraints = NIL;
					n->hasoids = $9;
					n->oncommit = $10;
					n->tablespacename = $11;
					$$ = (Node *)n;
				}
		| CREATE OptTemp TABLE qualified_name OF qualified_name
			'(' OptTableElementList ')' OptWithOids OnCommitOption OptTableSpace
				{
					/* SQL99 CREATE TABLE OF <UDT> (cols) seems to be satisfied
					 * by our inheritance capabilities. Let's try it...
					 */
					CreateStmt *n = makeNode(CreateStmt);
					$4->istemp = $2;
					n->relation = $4;
					n->tableElts = $8;
					n->inhRelations = list_make1($6);
					n->constraints = NIL;
					n->hasoids = $10;
					n->oncommit = $11;
					n->tablespacename = $12;
					$$ = (Node *)n;
				}
		;

/*
 * Redundancy here is needed to avoid shift/reduce conflicts,
 * since TEMP is not a reserved word.  See also OptTempTableName.
 *
 * NOTE: we accept both GLOBAL and LOCAL options; since we have no modules
 * the LOCAL keyword is really meaningless.
 */
OptTemp:	TEMPORARY						{ $$ = TRUE; }
			| TEMP							{ $$ = TRUE; }
			| LOCAL TEMPORARY				{ $$ = TRUE; }
			| LOCAL TEMP					{ $$ = TRUE; }
			| GLOBAL TEMPORARY				{ $$ = TRUE; }
			| GLOBAL TEMP					{ $$ = TRUE; }
			| /*EMPTY*/						{ $$ = FALSE; }
		;

OptTableElementList:
			TableElementList					{ $$ = $1; }
			| /*EMPTY*/							{ $$ = NIL; }
		;

TableElementList:
			TableElement
				{
					$$ = list_make1($1);
				}
			| TableElementList ',' TableElement
				{
					$$ = lappend($1, $3);
				}
		;

TableElement:
			columnDef							{ $$ = $1; }
			| TableLikeClause					{ $$ = $1; }
			| TableConstraint					{ $$ = $1; }
		;

columnDef:	ColId Typename ColQualList
				{
					ColumnDef *n = makeNode(ColumnDef);
					n->colname = $1;
					n->typename = $2;
					n->constraints = $3;
					n->is_local = true;
					$$ = (Node *)n;
				}
		;

ColQualList:
			ColQualList ColConstraint				{ $$ = lappend($1, $2); }
			| /*EMPTY*/								{ $$ = NIL; }
		;

ColConstraint:
			CONSTRAINT name ColConstraintElem
				{
					switch (nodeTag($3))
					{
						case T_Constraint:
							{
								Constraint *n = (Constraint *)$3;
								n->name = $2;
							}
							break;
						case T_FkConstraint:
							{
								FkConstraint *n = (FkConstraint *)$3;
								n->constr_name = $2;
							}
							break;
						default:
							break;
					}
					$$ = $3;
				}
			| ColConstraintElem						{ $$ = $1; }
			| ConstraintAttr						{ $$ = $1; }
		;

/* DEFAULT NULL is already the default for Postgres.
 * But define it here and carry it forward into the system
 * to make it explicit.
 * - thomas 1998-09-13
 *
 * WITH NULL and NULL are not SQL92-standard syntax elements,
 * so leave them out. Use DEFAULT NULL to explicitly indicate
 * that a column may have that value. WITH NULL leads to
 * shift/reduce conflicts with WITH TIME ZONE anyway.
 * - thomas 1999-01-08
 *
 * DEFAULT expression must be b_expr not a_expr to prevent shift/reduce
 * conflict on NOT (since NOT might start a subsequent NOT NULL constraint,
 * or be part of a_expr NOT LIKE or similar constructs).
 */
ColConstraintElem:
			NOT NULL_P
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_NOTNULL;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = NULL;
					$$ = (Node *)n;
				}
			| NULL_P
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_NULL;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = NULL;
					$$ = (Node *)n;
				}
			| UNIQUE OptConsTableSpace
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_UNIQUE;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = $2;
					$$ = (Node *)n;
				}
			| PRIMARY KEY OptConsTableSpace
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_PRIMARY;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = $3;
					$$ = (Node *)n;
				}
			| CHECK '(' a_expr ')'
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_CHECK;
					n->name = NULL;
					n->raw_expr = $3;
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = NULL;
					$$ = (Node *)n;
				}
			| DEFAULT b_expr
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_DEFAULT;
					n->name = NULL;
					if (exprIsNullConstant($2))
					{
						/* DEFAULT NULL should be reported as empty expr */
						n->raw_expr = NULL;
					}
					else
					{
						n->raw_expr = $2;
					}
					n->cooked_expr = NULL;
					n->keys = NULL;
					n->indexspace = NULL;
					$$ = (Node *)n;
				}
			| REFERENCES qualified_name opt_column_list key_match key_actions
				{
					FkConstraint *n = makeNode(FkConstraint);
					n->constr_name		= NULL;
					n->pktable			= $2;
					n->fk_attrs			= NIL;
					n->pk_attrs			= $3;
					n->fk_matchtype		= $4;
					n->fk_upd_action	= (char) ($5 >> 8);
					n->fk_del_action	= (char) ($5 & 0xFF);
					n->deferrable		= FALSE;
					n->initdeferred		= FALSE;
					$$ = (Node *)n;
				}
		;

/*
 * ConstraintAttr represents constraint attributes, which we parse as if
 * they were independent constraint clauses, in order to avoid shift/reduce
 * conflicts (since NOT might start either an independent NOT NULL clause
 * or an attribute).  analyze.c is responsible for attaching the attribute
 * information to the preceding "real" constraint node, and for complaining
 * if attribute clauses appear in the wrong place or wrong combinations.
 *
 * See also ConstraintAttributeSpec, which can be used in places where
 * there is no parsing conflict.
 */
ConstraintAttr:
			DEFERRABLE
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_ATTR_DEFERRABLE;
					$$ = (Node *)n;
				}
			| NOT DEFERRABLE
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_ATTR_NOT_DEFERRABLE;
					$$ = (Node *)n;
				}
			| INITIALLY DEFERRED
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_ATTR_DEFERRED;
					$$ = (Node *)n;
				}
			| INITIALLY IMMEDIATE
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_ATTR_IMMEDIATE;
					$$ = (Node *)n;
				}
		;


/*
 * SQL99 supports wholesale borrowing of a table definition via the LIKE clause.
 * This seems to be a poor man's inheritance capability, with the resulting
 * tables completely decoupled except for the original commonality in definitions.
 *
 * This is very similar to CREATE TABLE AS except for the INCLUDING DEFAULTS extension
 * which is a part of SQL 200N
 */
TableLikeClause:
			LIKE qualified_name like_including_defaults
				{
					InhRelation *n = makeNode(InhRelation);
					n->relation = $2;
					n->including_defaults = $3;

					$$ = (Node *)n;
				}
		;

like_including_defaults:
				INCLUDING DEFAULTS		{ $$ = true; }
				| EXCLUDING DEFAULTS		{ $$ = false; }
				| /* EMPTY */				{ $$ = false; }
		;


/* ConstraintElem specifies constraint syntax which is not embedded into
 *	a column definition. ColConstraintElem specifies the embedded form.
 * - thomas 1997-12-03
 */
TableConstraint:
			CONSTRAINT name ConstraintElem
				{
					switch (nodeTag($3))
					{
						case T_Constraint:
							{
								Constraint *n = (Constraint *)$3;
								n->name = $2;
							}
							break;
						case T_FkConstraint:
							{
								FkConstraint *n = (FkConstraint *)$3;
								n->constr_name = $2;
							}
							break;
						default:
							break;
					}
					$$ = $3;
				}
			| ConstraintElem						{ $$ = $1; }
		;

ConstraintElem:
			CHECK '(' a_expr ')'
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_CHECK;
					n->name = NULL;
					n->raw_expr = $3;
					n->cooked_expr = NULL;
					n->indexspace = NULL;
					$$ = (Node *)n;
				}
			| UNIQUE '(' columnList ')' OptConsTableSpace
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_UNIQUE;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = $3;
					n->indexspace = $5;
					$$ = (Node *)n;
				}
			| PRIMARY KEY '(' columnList ')' OptConsTableSpace
				{
					Constraint *n = makeNode(Constraint);
					n->contype = CONSTR_PRIMARY;
					n->name = NULL;
					n->raw_expr = NULL;
					n->cooked_expr = NULL;
					n->keys = $4;
					n->indexspace = $6;
					$$ = (Node *)n;
				}
			| FOREIGN KEY '(' columnList ')' REFERENCES qualified_name
				opt_column_list key_match key_actions ConstraintAttributeSpec
				{
					FkConstraint *n = makeNode(FkConstraint);
					n->constr_name		= NULL;
					n->pktable			= $7;
					n->fk_attrs			= $4;
					n->pk_attrs			= $8;
					n->fk_matchtype		= $9;
					n->fk_upd_action	= (char) ($10 >> 8);