codekingpro/portable-devtools

1/*-------------------------------------------------------------------------2 *3 * parse_node.h4 *		Internal definitions for parser5 *6 *7 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group8 * Portions Copyright (c) 1994, Regents of the University of California9 *10 * src/include/parser/parse_node.h11 *12 *-------------------------------------------------------------------------13 */14#ifndef PARSE_NODE_H15#define PARSE_NODE_H16 17#include "nodes/parsenodes.h"18#include "utils/queryenvironment.h"19#include "utils/relcache.h"20 21 22/* Forward references for some structs declared below */23typedef struct ParseState ParseState;24typedef struct ParseNamespaceItem ParseNamespaceItem;25typedef struct ParseNamespaceColumn ParseNamespaceColumn;26 27/*28 * Expression kinds distinguished by transformExpr().  Many of these are not29 * semantically distinct so far as expression transformation goes; rather,30 * we distinguish them so that context-specific error messages can be printed.31 *32 * Note: EXPR_KIND_OTHER is not used in the core code, but is left for use33 * by extension code that might need to call transformExpr().  The core code34 * will not enforce any context-driven restrictions on EXPR_KIND_OTHER35 * expressions, so the caller would have to check for sub-selects, aggregates,36 * window functions, SRFs, etc if those need to be disallowed.37 */38typedef enum ParseExprKind39{40	EXPR_KIND_NONE = 0,			/* "not in an expression" */41	EXPR_KIND_OTHER,			/* reserved for extensions */42	EXPR_KIND_JOIN_ON,			/* JOIN ON */43	EXPR_KIND_JOIN_USING,		/* JOIN USING */44	EXPR_KIND_FROM_SUBSELECT,	/* sub-SELECT in FROM clause */45	EXPR_KIND_FROM_FUNCTION,	/* function in FROM clause */46	EXPR_KIND_WHERE,			/* WHERE */47	EXPR_KIND_HAVING,			/* HAVING */48	EXPR_KIND_FILTER,			/* FILTER */49	EXPR_KIND_WINDOW_PARTITION, /* window definition PARTITION BY */50	EXPR_KIND_WINDOW_ORDER,		/* window definition ORDER BY */51	EXPR_KIND_WINDOW_FRAME_RANGE,	/* window frame clause with RANGE */52	EXPR_KIND_WINDOW_FRAME_ROWS,	/* window frame clause with ROWS */53	EXPR_KIND_WINDOW_FRAME_GROUPS,	/* window frame clause with GROUPS */54	EXPR_KIND_SELECT_TARGET,	/* SELECT target list item */55	EXPR_KIND_INSERT_TARGET,	/* INSERT target list item */56	EXPR_KIND_UPDATE_SOURCE,	/* UPDATE assignment source item */57	EXPR_KIND_UPDATE_TARGET,	/* UPDATE assignment target item */58	EXPR_KIND_MERGE_WHEN,		/* MERGE WHEN [NOT] MATCHED condition */59	EXPR_KIND_GROUP_BY,			/* GROUP BY */60	EXPR_KIND_ORDER_BY,			/* ORDER BY */61	EXPR_KIND_DISTINCT_ON,		/* DISTINCT ON */62	EXPR_KIND_LIMIT,			/* LIMIT */63	EXPR_KIND_OFFSET,			/* OFFSET */64	EXPR_KIND_RETURNING,		/* RETURNING */65	EXPR_KIND_VALUES,			/* VALUES */66	EXPR_KIND_VALUES_SINGLE,	/* single-row VALUES (in INSERT only) */67	EXPR_KIND_CHECK_CONSTRAINT, /* CHECK constraint for a table */68	EXPR_KIND_DOMAIN_CHECK,		/* CHECK constraint for a domain */69	EXPR_KIND_COLUMN_DEFAULT,	/* default value for a table column */70	EXPR_KIND_FUNCTION_DEFAULT, /* default parameter value for function */71	EXPR_KIND_INDEX_EXPRESSION, /* index expression */72	EXPR_KIND_INDEX_PREDICATE,	/* index predicate */73	EXPR_KIND_STATS_EXPRESSION, /* extended statistics expression */74	EXPR_KIND_ALTER_COL_TRANSFORM,	/* transform expr in ALTER COLUMN TYPE */75	EXPR_KIND_EXECUTE_PARAMETER,	/* parameter value in EXECUTE */76	EXPR_KIND_TRIGGER_WHEN,		/* WHEN condition in CREATE TRIGGER */77	EXPR_KIND_POLICY,			/* USING or WITH CHECK expr in policy */78	EXPR_KIND_PARTITION_BOUND,	/* partition bound expression */79	EXPR_KIND_PARTITION_EXPRESSION, /* PARTITION BY expression */80	EXPR_KIND_CALL_ARGUMENT,	/* procedure argument in CALL */81	EXPR_KIND_COPY_WHERE,		/* WHERE condition in COPY FROM */82	EXPR_KIND_GENERATED_COLUMN, /* generation expression for a column */83	EXPR_KIND_CYCLE_MARK,		/* cycle mark value */84} ParseExprKind;85 86 87/*88 * Function signatures for parser hooks89 */90typedef Node *(*PreParseColumnRefHook) (ParseState *pstate, ColumnRef *cref);91typedef Node *(*PostParseColumnRefHook) (ParseState *pstate, ColumnRef *cref, Node *var);92typedef Node *(*ParseParamRefHook) (ParseState *pstate, ParamRef *pref);93typedef Node *(*CoerceParamHook) (ParseState *pstate, Param *param,94								  Oid targetTypeId, int32 targetTypeMod,95								  int location);96 97 98/*99 * State information used during parse analysis100 *101 * parentParseState: NULL in a top-level ParseState.  When parsing a subquery,102 * links to current parse state of outer query.103 *104 * p_sourcetext: source string that generated the raw parsetree being105 * analyzed, or NULL if not available.  (The string is used only to106 * generate cursor positions in error messages: we need it to convert107 * byte-wise locations in parse structures to character-wise cursor108 * positions.)109 *110 * p_rtable: list of RTEs that will become the rangetable of the query.111 * Note that neither relname nor refname of these entries are necessarily112 * unique; searching the rtable by name is a bad idea.113 *114 * p_rteperminfos: list of RTEPermissionInfo containing an entry corresponding115 * to each RTE_RELATION entry in p_rtable.116 *117 * p_joinexprs: list of JoinExpr nodes associated with p_rtable entries.118 * This is one-for-one with p_rtable, but contains NULLs for non-join119 * RTEs, and may be shorter than p_rtable if the last RTE(s) aren't joins.120 *121 * p_nullingrels: list of Bitmapsets associated with p_rtable entries, each122 * containing the set of outer-join RTE indexes that can null that relation123 * at the current point in the parse tree.  This is one-for-one with p_rtable,124 * but may be shorter than p_rtable, in which case the missing entries are125 * implicitly empty (NULL).  That rule allows us to save work when the query126 * contains no outer joins.127 *128 * p_joinlist: list of join items (RangeTblRef and JoinExpr nodes) that129 * will become the fromlist of the query's top-level FromExpr node.130 *131 * p_namespace: list of ParseNamespaceItems that represents the current132 * namespace for table and column lookup.  (The RTEs listed here may be just133 * a subset of the whole rtable.  See ParseNamespaceItem comments below.)134 *135 * p_lateral_active: true if we are currently parsing a LATERAL subexpression136 * of this parse level.  This makes p_lateral_only namespace items visible,137 * whereas they are not visible when p_lateral_active is FALSE.138 *139 * p_ctenamespace: list of CommonTableExprs (WITH items) that are visible140 * at the moment.  This is entirely different from p_namespace because a CTE141 * is not an RTE, rather "visibility" means you could make an RTE from it.142 *143 * p_future_ctes: list of CommonTableExprs (WITH items) that are not yet144 * visible due to scope rules.  This is used to help improve error messages.145 *146 * p_parent_cte: CommonTableExpr that immediately contains the current query,147 * if any.148 *149 * p_target_relation: target relation, if query is INSERT/UPDATE/DELETE/MERGE150 *151 * p_target_nsitem: target relation's ParseNamespaceItem.152 *153 * p_is_insert: true to process assignment expressions like INSERT, false154 * to process them like UPDATE.  (Note this can change intra-statement, for155 * cases like INSERT ON CONFLICT UPDATE.)156 *157 * p_windowdefs: list of WindowDefs representing WINDOW and OVER clauses.158 * We collect these while transforming expressions and then transform them159 * afterwards (so that any resjunk tlist items needed for the sort/group160 * clauses end up at the end of the query tlist).  A WindowDef's location in161 * this list, counting from 1, is the winref number to use to reference it.162 *163 * p_expr_kind: kind of expression we're currently parsing, as per enum above;164 * EXPR_KIND_NONE when not in an expression.165 *166 * p_next_resno: next TargetEntry.resno to assign, starting from 1.167 *168 * p_multiassign_exprs: partially-processed MultiAssignRef source expressions.169 *170 * p_locking_clause: query's FOR UPDATE/FOR SHARE clause, if any.171 *172 * p_locked_from_parent: true if parent query level applies FOR UPDATE/SHARE173 * to this subquery as a whole.174 *175 * p_resolve_unknowns: resolve unknown-type SELECT output columns as type TEXT176 * (this is true by default).177 *178 * p_hasAggs, p_hasWindowFuncs, etc: true if we've found any of the indicated179 * constructs in the query.180 *181 * p_last_srf: the set-returning FuncExpr or OpExpr most recently found in182 * the query, or NULL if none.183 *184 * p_pre_columnref_hook, etc: optional parser hook functions for modifying the185 * interpretation of ColumnRefs and ParamRefs.186 *187 * p_ref_hook_state: passthrough state for the parser hook functions.188 */189struct ParseState190{191	ParseState *parentParseState;	/* stack link */192	const char *p_sourcetext;	/* source text, or NULL if not available */193	List	   *p_rtable;		/* range table so far */194	List	   *p_rteperminfos; /* list of RTEPermissionInfo nodes for each195								 * RTE_RELATION entry in rtable */196	List	   *p_joinexprs;	/* JoinExprs for RTE_JOIN p_rtable entries */197	List	   *p_nullingrels;	/* Bitmapsets showing nulling outer joins */198	List	   *p_joinlist;		/* join items so far (will become FromExpr199								 * node's fromlist) */200	List	   *p_namespace;	/* currently-referenceable RTEs (List of201								 * ParseNamespaceItem) */202	bool		p_lateral_active;	/* p_lateral_only items visible? */203	List	   *p_ctenamespace; /* current namespace for common table exprs */204	List	   *p_future_ctes;	/* common table exprs not yet in namespace */205	CommonTableExpr *p_parent_cte;	/* this query's containing CTE */206	Relation	p_target_relation;	/* INSERT/UPDATE/DELETE/MERGE target rel */207	ParseNamespaceItem *p_target_nsitem;	/* target rel's NSItem, or NULL */208	bool		p_is_insert;	/* process assignment like INSERT not UPDATE */209	List	   *p_windowdefs;	/* raw representations of window clauses */210	ParseExprKind p_expr_kind;	/* what kind of expression we're parsing */211	int			p_next_resno;	/* next targetlist resno to assign */212	List	   *p_multiassign_exprs;	/* junk tlist entries for multiassign */213	List	   *p_locking_clause;	/* raw FOR UPDATE/FOR SHARE info */214	bool		p_locked_from_parent;	/* parent has marked this subquery215										 * with FOR UPDATE/FOR SHARE */216	bool		p_resolve_unknowns; /* resolve unknown-type SELECT outputs as217									 * type text */218 219	QueryEnvironment *p_queryEnv;	/* curr env, incl refs to enclosing env */220 221	/* Flags telling about things found in the query: */222	bool		p_hasAggs;223	bool		p_hasWindowFuncs;224	bool		p_hasTargetSRFs;225	bool		p_hasSubLinks;226	bool		p_hasModifyingCTE;227 228	Node	   *p_last_srf;		/* most recent set-returning func/op found */229 230	/*231	 * Optional hook functions for parser callbacks.  These are null unless232	 * set up by the caller of make_parsestate.233	 */234	PreParseColumnRefHook p_pre_columnref_hook;235	PostParseColumnRefHook p_post_columnref_hook;236	ParseParamRefHook p_paramref_hook;237	CoerceParamHook p_coerce_param_hook;238	void	   *p_ref_hook_state;	/* common passthrough link for above */239};240 241/*242 * An element of a namespace list.243 *244 * p_names contains the table name and column names exposed by this nsitem.245 * (Typically it's equal to p_rte->eref, but for a JOIN USING alias it's246 * equal to p_rte->join_using_alias.  Since the USING columns will be the247 * join's first N columns, the net effect is just that we expose only those248 * join columns via this nsitem.)249 *250 * p_rte and p_rtindex link to the underlying rangetable entry, and251 * p_perminfo to the entry in rteperminfos.252 *253 * The p_nscolumns array contains info showing how to construct Vars254 * referencing the names appearing in the p_names->colnames list.255 *256 * Namespace items with p_rel_visible set define which RTEs are accessible by257 * qualified names, while those with p_cols_visible set define which RTEs are258 * accessible by unqualified names.  These sets are different because a JOIN259 * without an alias does not hide the contained tables (so they must be260 * visible for qualified references) but it does hide their columns261 * (unqualified references to the columns refer to the JOIN, not the member262 * tables, so we must not complain that such a reference is ambiguous).263 * Conversely, a subquery without an alias does not hide the columns selected264 * by the subquery, but it does hide the auto-generated relation name (so the265 * subquery columns are visible for unqualified references only).  Various266 * special RTEs such as NEW/OLD for rules may also appear with only one flag267 * set.268 *269 * While processing the FROM clause, namespace items may appear with270 * p_lateral_only set, meaning they are visible only to LATERAL271 * subexpressions.  (The pstate's p_lateral_active flag tells whether we are272 * inside such a subexpression at the moment.)	If p_lateral_ok is not set,273 * it's an error to actually use such a namespace item.  One might think it274 * would be better to just exclude such items from visibility, but the wording275 * of SQL:2008 requires us to do it this way.  We also use p_lateral_ok to276 * forbid LATERAL references to an UPDATE/DELETE target table.277 *278 * At no time should a namespace list contain two entries that conflict279 * according to the rules in checkNameSpaceConflicts; but note that those280 * are more complicated than "must have different alias names", so in practice281 * code searching a namespace list has to check for ambiguous references.282 */283struct ParseNamespaceItem284{285	Alias	   *p_names;		/* Table and column names */286	RangeTblEntry *p_rte;		/* The relation's rangetable entry */287	int			p_rtindex;		/* The relation's index in the rangetable */288	RTEPermissionInfo *p_perminfo;	/* The relation's rteperminfos entry */289	/* array of same length as p_names->colnames: */290	ParseNamespaceColumn *p_nscolumns;	/* per-column data */291	bool		p_rel_visible;	/* Relation name is visible? */292	bool		p_cols_visible; /* Column names visible as unqualified refs? */293	bool		p_lateral_only; /* Is only visible to LATERAL expressions? */294	bool		p_lateral_ok;	/* If so, does join type allow use? */295};296 297/*298 * Data about one column of a ParseNamespaceItem.299 *300 * We track the info needed to construct a Var referencing the column301 * (but only for user-defined columns; system column references and302 * whole-row references are handled separately).303 *304 * p_varno and p_varattno identify the semantic referent, which is a305 * base-relation column unless the reference is to a join USING column that306 * isn't semantically equivalent to either join input column (because it is a307 * FULL join or the input column requires a type coercion).  In those cases308 * p_varno and p_varattno refer to the JOIN RTE.309 *310 * p_varnosyn and p_varattnosyn are either identical to p_varno/p_varattno,311 * or they specify the column's position in an aliased JOIN RTE that hides312 * the semantic referent RTE's refname.  (That could be either the JOIN RTE313 * in which this ParseNamespaceColumn entry exists, or some lower join level.)314 *315 * If an RTE contains a dropped column, its ParseNamespaceColumn struct316 * is all-zeroes.  (Conventionally, test for p_varno == 0 to detect this.)317 */318struct ParseNamespaceColumn319{320	Index		p_varno;		/* rangetable index */321	AttrNumber	p_varattno;		/* attribute number of the column */322	Oid			p_vartype;		/* pg_type OID */323	int32		p_vartypmod;	/* type modifier value */324	Oid			p_varcollid;	/* OID of collation, or InvalidOid */325	Index		p_varnosyn;		/* rangetable index of syntactic referent */326	AttrNumber	p_varattnosyn;	/* attribute number of syntactic referent */327	bool		p_dontexpand;	/* not included in star expansion */328};329 330/* Support for parser_errposition_callback function */331typedef struct ParseCallbackState332{333	ParseState *pstate;334	int			location;335	ErrorContextCallback errcallback;336} ParseCallbackState;337 338 339extern ParseState *make_parsestate(ParseState *parentParseState);340extern void free_parsestate(ParseState *pstate);341extern int	parser_errposition(ParseState *pstate, int location);342 343extern void setup_parser_errposition_callback(ParseCallbackState *pcbstate,344											  ParseState *pstate, int location);345extern void cancel_parser_errposition_callback(ParseCallbackState *pcbstate);346 347extern void transformContainerType(Oid *containerType, int32 *containerTypmod);348 349extern SubscriptingRef *transformContainerSubscripts(ParseState *pstate,350													 Node *containerBase,351													 Oid containerType,352													 int32 containerTypMod,353													 List *indirection,354													 bool isAssignment);355extern Const *make_const(ParseState *pstate, A_Const *aconst);356 357#endif							/* PARSE_NODE_H */358