gram.y

PostgreSQL7.4.6 for Linux

%{

/*#define YYDEBUG 1*/
/*-------------------------------------------------------------------------
 *
 * gram.y
 *	  POSTGRES SQL YACC rules/actions
 *
 * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group
 * Portions Copyright (c) 1994, Regents of the University of California
 *
 *
 * IDENTIFICATION
 *	  $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 2.436.2.1 2003/11/24 16:54:15 tgl Exp $
 *
 * HISTORY
 *	  AUTHOR			DATE			MAJOR EVENT
 *	  Andrew Yu			Sept, 1994		POSTQUEL to SQL conversion
 *	  Andrew Yu			Oct, 1994		lispy code conversion
 *
 * NOTES
 *	  CAPITALS are used to represent terminal symbols.
 *	  non-capitals are used to represent non-terminals.
 *	  SQL92-specific syntax is separated from plain SQL/Postgres syntax
 *	  to help isolate the non-extensible portions of the parser.
 *
 *	  In general, nothing in this file should initiate database accesses
 *	  nor depend on changeable state (such as SET variables).  If you do
 *	  database accesses, your code will fail when we have aborted the
 *	  current transaction and are just parsing commands to find the next
 *	  ROLLBACK or COMMIT.  If you make use of SET variables, then you
 *	  will do the wrong thing in multi-query strings like this:
 *			SET SQL_inheritance TO off; SELECT * FROM foo;
 *	  because the entire string is parsed by gram.y before the SET gets
 *	  executed.  Anything that depends on the database or changeable state
 *	  should be handled inside parse_analyze() so that it happens at the
 *	  right time not the wrong time.  The handling of SQL_inheritance is
 *	  a good example.
 *
 * WARNINGS
 *	  If you use a list, make sure the datum is a node so that the printing
 *	  routines work.
 *
 *	  Sometimes we assign constants to makeStrings. Make sure we don't free
 *	  those.
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"

#include <ctype.h>
#include <limits.h>

#include "access/htup.h"
#include "catalog/index.h"
#include "catalog/namespace.h"
#include "catalog/pg_type.h"
#include "nodes/makefuncs.h"
#include "nodes/params.h"
#include "nodes/parsenodes.h"
#include "parser/gramparse.h"
#include "storage/lmgr.h"
#include "utils/numeric.h"
#include "utils/datetime.h"
#include "utils/date.h"

extern List *parsetree;			/* final parse result is delivered here */

static bool QueryIsRule = FALSE;

/*
 * If you need access to certain yacc-generated variables and find that
 * they're static by default, uncomment the next line.  (this is not a
 * problem, yet.)
 */
/*#define __YYSCLASS*/

static Node *makeTypeCast(Node *arg, TypeName *typename);
static Node *makeStringConst(char *str, TypeName *typename);
static Node *makeIntConst(int val);
static Node *makeFloatConst(char *str);
static Node *makeAConst(Value *v);
static Node *makeRowExpr(List *opr, List *largs, List *rargs);
static Node *makeDistinctExpr(List *largs, List *rargs);
static Node *makeRowNullTest(NullTestType test, List *args);
static DefElem *makeDefElem(char *name, Node *arg);
static A_Const *makeBoolConst(bool state);
static FuncCall *makeOverlaps(List *largs, List *rargs);
static SelectStmt *findLeftmostSelect(SelectStmt *node);
static void insertSelectOptions(SelectStmt *stmt,
								List *sortClause, List *forUpdate,
								Node *limitOffset, Node *limitCount);
static Node *makeSetOp(SetOperation op, bool all, Node *larg, Node *rarg);
static Node *doNegate(Node *n);
static void doNegateFloat(Value *v);

%}


%union
{
	int					ival;
	char				chr;
	char				*str;
	const char			*keyword;
	bool				boolean;
	JoinType			jtype;
	DropBehavior		dbehavior;
	OnCommitAction		oncommit;
	List				*list;
	FastList			fastlist;
	Node				*node;
	Value				*value;
	ColumnRef			*columnref;
	ObjectType			objtype;

	TypeName			*typnam;
	DefElem				*defelt;
	SortBy				*sortby;
	JoinExpr			*jexpr;
	IndexElem			*ielem;
	Alias				*alias;
	RangeVar			*range;
	A_Indices			*aind;
	ResTarget			*target;
	PrivTarget			*privtarget;

	InsertStmt			*istmt;
	VariableSetStmt		*vsetstmt;
}

%type <node>	stmt schema_stmt
		AlterDatabaseSetStmt AlterDomainStmt AlterGroupStmt
		AlterSeqStmt AlterTableStmt AlterUserStmt AlterUserSetStmt
		AnalyzeStmt ClosePortalStmt ClusterStmt CommentStmt
		ConstraintsSetStmt CopyStmt CreateAsStmt CreateCastStmt
		CreateDomainStmt CreateGroupStmt CreateOpClassStmt CreatePLangStmt
		CreateSchemaStmt CreateSeqStmt CreateStmt
		CreateAssertStmt CreateTrigStmt CreateUserStmt
		CreatedbStmt DeclareCursorStmt DefineStmt DeleteStmt
		DropGroupStmt DropOpClassStmt DropPLangStmt DropStmt
		DropAssertStmt DropTrigStmt DropRuleStmt DropCastStmt
		DropUserStmt DropdbStmt ExplainStmt FetchStmt
		GrantStmt IndexStmt InsertStmt ListenStmt LoadStmt
		LockStmt NotifyStmt ExplainableStmt PreparableStmt
		CreateFunctionStmt ReindexStmt RemoveAggrStmt
		RemoveFuncStmt RemoveOperStmt RenameStmt RevokeStmt
		RuleActionStmt RuleActionStmtOrEmpty RuleStmt
		SelectStmt TransactionStmt TruncateStmt
		UnlistenStmt UpdateStmt VacuumStmt
		VariableResetStmt VariableSetStmt VariableShowStmt
		ViewStmt CheckPointStmt CreateConversionStmt
		DeallocateStmt PrepareStmt ExecuteStmt

%type <node>	select_no_parens select_with_parens select_clause
				simple_select

%type <node>	alter_column_default opclass_item
%type <ival>	add_drop

%type <dbehavior>	opt_drop_behavior

%type <list>	createdb_opt_list copy_opt_list
%type <defelt>	createdb_opt_item copy_opt_item

%type <ival>	opt_lock lock_type cast_context
%type <boolean>	opt_force opt_or_replace transaction_access_mode
				opt_grant_grant_option opt_revoke_grant_option

%type <boolean>	like_including_defaults

%type <list>	user_list

%type <list>	OptGroupList
%type <defelt>	OptGroupElem

%type <list>	OptUserList
%type <defelt>	OptUserElem

%type <str>		OptSchemaName
%type <list>	OptSchemaEltList

%type <boolean> TriggerActionTime TriggerForSpec opt_trusted
%type <str>		opt_lancompiler

%type <str>		TriggerEvents
%type <value>	TriggerFuncArg

%type <str>		relation_name copy_file_name
				database_name access_method_clause access_method attr_name
				index_name name function_name file_name

%type <list>	func_name handler_name qual_Op qual_all_Op
				opt_class opt_validator

%type <range>	qualified_name OptConstrFromTable

%type <str>		all_Op MathOp opt_name SpecialRuleRelation

%type <str>		iso_level opt_encoding
%type <node>	grantee
%type <list>	grantee_list
%type <ival>	privilege
%type <list>	privileges privilege_list
%type <privtarget> privilege_target
%type <node>	function_with_argtypes
%type <list>	function_with_argtypes_list
%type <chr> 	TriggerOneEvent

%type <list>	stmtblock stmtmulti
				OptTableElementList TableElementList OptInherit definition
				opt_distinct opt_definition func_args
				func_args_list func_as createfunc_opt_list
				oper_argtypes RuleActionList RuleActionMulti
				opt_column_list columnList opt_name_list
				sort_clause opt_sort_clause sortby_list index_params
				name_list from_clause from_list opt_array_bounds
				qualified_name_list any_name any_name_list
				any_operator expr_list dotted_name attrs
				target_list update_target_list insert_column_list
				insert_target_list def_list opt_indirection
				group_clause TriggerFuncArgs select_limit
				opt_select_limit opclass_item_list transaction_mode_list
				transaction_mode_list_or_empty
				TableFuncElementList
				prep_type_clause prep_type_list
				execute_param_clause

%type <range>	into_clause OptTempTableName

%type <defelt>	createfunc_opt_item
%type <typnam>	func_arg func_return func_type aggr_argtype

%type <boolean> opt_arg TriggerForType OptTemp OptWithOids
%type <oncommit>	OnCommitOption

%type <list>	for_update_clause opt_for_update_clause update_list
%type <boolean>	opt_all

%type <node>	join_outer join_qual
%type <jtype>	join_type

%type <list>	extract_list overlay_list position_list
%type <list>	substr_list trim_list
%type <ival>	opt_interval
%type <node>	overlay_placing substr_from substr_for

%type <boolean> opt_instead opt_analyze
%type <boolean> index_opt_unique opt_verbose opt_full
%type <boolean> opt_freeze opt_default opt_recheck
%type <defelt>	opt_binary opt_oids copy_delimiter

%type <boolean> copy_from opt_hold

%type <ival>	fetch_count	opt_column event cursor_options
%type <objtype>	reindex_type drop_type comment_type

%type <node>	fetch_direction select_limit_value select_offset_value

%type <list>	OptSeqList
%type <defelt>	OptSeqElem

%type <istmt>	insert_rest

%type <vsetstmt> set_rest

%type <node>	TableElement ConstraintElem TableFuncElement
%type <node>	columnDef
%type <defelt>	def_elem
%type <node>	def_arg columnElem where_clause insert_column_item
				a_expr b_expr c_expr r_expr AexprConst
				in_expr having_clause func_table array_expr
%type <list>	row row_descriptor type_list array_expr_list
%type <node>	case_expr case_arg when_clause case_default
%type <list>	when_clause_list
%type <ival>	sub_type
%type <list>	OptCreateAs CreateAsList
%type <node>	CreateAsElement
%type <value>	NumericOnly FloatOnly IntegerOnly
%type <columnref>	columnref
%type <alias>	alias_clause
%type <sortby>	sortby
%type <ielem>	index_elem
%type <node>	table_ref
%type <jexpr>	joined_table
%type <range>	relation_expr
%type <target>	target_el insert_target_el update_target_el

%type <typnam>	Typename SimpleTypename ConstTypename
				GenericType Numeric opt_float
				Character ConstCharacter
				CharacterWithLength CharacterWithoutLength
				ConstDatetime ConstInterval
				Bit ConstBit BitWithLength BitWithoutLength
%type <str>		character
%type <str>		extract_arg
%type <str>		opt_charset
%type <ival>	opt_numeric opt_decimal
%type <boolean> opt_varying opt_timezone

%type <ival>	Iconst
%type <str>		Sconst comment_text
%type <str>		UserId opt_boolean ColId_or_Sconst
%type <list>	var_list var_list_or_default
%type <str>		ColId ColLabel type_name
%type <node>	var_value zone_value

%type <keyword> unreserved_keyword func_name_keyword
%type <keyword> col_name_keyword reserved_keyword

%type <node>	TableConstraint TableLikeClause
%type <list>	ColQualList
%type <node>	ColConstraint ColConstraintElem ConstraintAttr
%type <ival>	key_actions key_delete key_match key_update key_action
%type <ival>	ConstraintAttributeSpec ConstraintDeferrabilitySpec
				ConstraintTimeSpec

%type <list>	constraints_set_list
%type <boolean> constraints_set_mode


/*
 * If you make any token changes, update the keyword table in
 * parser/keywords.c and add new keywords to the appropriate one of
 * the reserved-or-not-so-reserved keyword lists, below.
 */

/* ordinary key words in alphabetical order */
%token <keyword> ABORT_P ABSOLUTE_P ACCESS ACTION ADD AFTER
	AGGREGATE ALL ALTER ANALYSE ANALYZE AND ANY ARRAY AS ASC
	ASSERTION ASSIGNMENT AT AUTHORIZATION

	BACKWARD BEFORE BEGIN_P BETWEEN BIGINT BINARY BIT
	BOOLEAN_P BOTH BY

	CACHE CALLED CASCADE CASE CAST CHAIN CHAR_P
	CHARACTER CHARACTERISTICS CHECK CHECKPOINT CLASS CLOSE
	CLUSTER COALESCE COLLATE COLUMN COMMENT COMMIT
	COMMITTED CONSTRAINT CONSTRAINTS CONVERSION_P CONVERT COPY CREATE CREATEDB
	CREATEUSER CROSS CURRENT_DATE CURRENT_TIME
	CURRENT_TIMESTAMP CURRENT_USER CURSOR CYCLE

	DATABASE DAY_P DEALLOCATE DEC DECIMAL_P DECLARE DEFAULT DEFAULTS
	DEFERRABLE DEFERRED DEFINER DELETE_P DELIMITER DELIMITERS
    DESC DISTINCT DO DOMAIN_P DOUBLE_P DROP

	EACH ELSE ENCODING ENCRYPTED END_P ESCAPE EXCEPT EXCLUDING
	EXCLUSIVE EXECUTE EXISTS EXPLAIN EXTERNAL EXTRACT

	FALSE_P FETCH FIRST_P FLOAT_P FOR FORCE FOREIGN FORWARD
	FREEZE FROM FULL FUNCTION

	GLOBAL GRANT GROUP_P

	HANDLER HAVING HOLD HOUR_P

	ILIKE IMMEDIATE IMMUTABLE IMPLICIT_P IN_P INCLUDING INCREMENT
	INDEX INHERITS INITIALLY INNER_P INOUT INPUT_P
	INSENSITIVE INSERT INSTEAD INT_P INTEGER INTERSECT
	INTERVAL INTO INVOKER IS ISNULL ISOLATION

	JOIN

	KEY

	LANCOMPILER LANGUAGE LAST_P LEADING LEFT LEVEL LIKE LIMIT
	LISTEN LOAD LOCAL LOCALTIME LOCALTIMESTAMP LOCATION
	LOCK_P

	MATCH MAXVALUE MINUTE_P MINVALUE MODE MONTH_P MOVE

	NAMES NATIONAL NATURAL NCHAR NEW NEXT NO NOCREATEDB
	NOCREATEUSER NONE NOT NOTHING NOTIFY NOTNULL NULL_P
	NULLIF NUMERIC

	OF OFF OFFSET OIDS OLD ON ONLY OPERATOR OPTION OR
	ORDER OUT_P OUTER_P OVERLAPS OVERLAY OWNER

	PARTIAL PASSWORD PATH_P PENDANT PLACING POSITION
	PRECISION PRESERVE PREPARE PRIMARY 
	PRIOR PRIVILEGES PROCEDURAL PROCEDURE

	READ REAL RECHECK REFERENCES REINDEX RELATIVE_P RENAME REPLACE
	RESET RESTART RESTRICT RETURNS REVOKE RIGHT ROLLBACK ROW ROWS
	RULE

	SCHEMA SCROLL SECOND_P SECURITY SELECT SEQUENCE
	SERIALIZABLE SESSION SESSION_USER SET SETOF SHARE
	SHOW SIMILAR SIMPLE SMALLINT SOME STABLE START STATEMENT
	STATISTICS STDIN STDOUT STORAGE STRICT_P SUBSTRING SYSID

	TABLE TEMP TEMPLATE TEMPORARY THEN TIME TIMESTAMP
	TO TOAST TRAILING TRANSACTION TREAT TRIGGER TRIM TRUE_P
	TRUNCATE TRUSTED TYPE_P

	UNENCRYPTED UNION UNIQUE UNKNOWN UNLISTEN UNTIL
	UPDATE USAGE USER USING

	VACUUM VALID VALIDATOR VALUES VARCHAR VARYING
	VERBOSE VERSION VIEW VOLATILE

	WHEN WHERE WITH WITHOUT WORK WRITE

	YEAR_P

	ZONE

/* The grammar thinks these are keywords, but they are not in the keywords.c
 * list and so can never be entered directly.  The filter in parser.c
 * creates these tokens when required.
 */
%token			UNIONJOIN

/* Special keywords, not in the query language - see the "lex" file */
%token <str>	IDENT FCONST SCONST BCONST XCONST Op
%token <ival>	ICONST PARAM

/* precedence: lowest to highest */
%left		UNION EXCEPT
%left		INTERSECT
%left		OR
%left		AND
%right		NOT
%right		'='
%nonassoc	'<' '>'
%nonassoc	LIKE ILIKE SIMILAR
%nonassoc	ESCAPE
%nonassoc	OVERLAPS
%nonassoc	BETWEEN
%nonassoc	IN_P
%left		POSTFIXOP		/* dummy for postfix Op rules */
%left		Op OPERATOR		/* multi-character ops and user-defined operators */
%nonassoc	NOTNULL
%nonassoc	ISNULL
%nonassoc	IS NULL_P TRUE_P FALSE_P UNKNOWN /* sets precedence for IS NULL, etc */
%left		'+' '-'
%left		'*' '/' '%'
%left		'^'
/* Unary Operators */
%left		AT ZONE			/* sets precedence for AT TIME ZONE */
%right		UMINUS
%left		'[' ']'
%left		'(' ')'
%left		TYPECAST
%left		'.'
/*
 * These might seem to be low-precedence, but actually they are not part
 * of the arithmetic hierarchy at all in their use as JOIN operators.
 * We make them high-precedence to support their use as function names.
 * They wouldn't be given a precedence at all, were it not that we need
 * left-associativity among the JOIN rules themselves.
 */
%left		JOIN UNIONJOIN CROSS LEFT FULL RIGHT INNER_P NATURAL
%%

/*
 *	Handle comment-only lines, and ;; SELECT * FROM pg_class ;;;
 *	psql already handles such cases, but other interfaces don't.
 *	bjm 1999/10/05
 */
stmtblock:	stmtmulti								{ parsetree = $1; }
		;

/* the thrashing around here is to discard "empty" statements... */
stmtmulti:	stmtmulti ';' stmt
				{ if ($3 != (Node *)NULL)
					$$ = lappend($1, $3);
				  else
					$$ = $1;
				}
			| stmt
					{ if ($1 != (Node *)NULL)
						$$ = makeList1($1);
					  else
						$$ = NIL;
					}
		;

stmt :
			AlterDatabaseSetStmt
			| AlterDomainStmt
			| AlterGroupStmt
			| AlterSeqStmt
			| AlterTableStmt
			| AlterUserSetStmt
			| AlterUserStmt
			| AnalyzeStmt
			| CheckPointStmt
			| ClosePortalStmt
			| ClusterStmt
			| CommentStmt
			| ConstraintsSetStmt
			| CopyStmt
			| CreateAsStmt
			| CreateAssertStmt
			| CreateCastStmt
			| CreateConversionStmt
			| CreateDomainStmt
			| CreateFunctionStmt
			| CreateGroupStmt
			| CreateOpClassStmt
			| CreatePLangStmt
			| CreateSchemaStmt
			| CreateSeqStmt
			| CreateStmt
			| CreateTrigStmt
			| CreateUserStmt
			| CreatedbStmt
			| DeallocateStmt
			| DeclareCursorStmt
			| DefineStmt
			| DeleteStmt
			| DropAssertStmt
			| DropCastStmt
			| DropGroupStmt
			| DropOpClassStmt
			| DropPLangStmt