diff options
Diffstat (limited to 'src/include/parser/parse_node.h')
| -rw-r--r-- | src/include/parser/parse_node.h | 57 |
1 files changed, 47 insertions, 10 deletions
diff --git a/src/include/parser/parse_node.h b/src/include/parser/parse_node.h index 8e71b2ed5fc..d25819aa28b 100644 --- a/src/include/parser/parse_node.h +++ b/src/include/parser/parse_node.h @@ -19,6 +19,11 @@ #include "utils/relcache.h" +/* Forward references for some structs declared below */ +typedef struct ParseState ParseState; +typedef struct ParseNamespaceItem ParseNamespaceItem; +typedef struct ParseNamespaceColumn ParseNamespaceColumn; + /* * Expression kinds distinguished by transformExpr(). Many of these are not * semantically distinct so far as expression transformation goes; rather, @@ -79,8 +84,6 @@ typedef enum ParseExprKind /* * Function signatures for parser hooks */ -typedef struct ParseState ParseState; - typedef Node *(*PreParseColumnRefHook) (ParseState *pstate, ColumnRef *cref); typedef Node *(*PostParseColumnRefHook) (ParseState *pstate, ColumnRef *cref, Node *var); typedef Node *(*ParseParamRefHook) (ParseState *pstate, ParamRef *pref); @@ -132,9 +135,7 @@ typedef Node *(*CoerceParamHook) (ParseState *pstate, Param *param, * * p_target_relation: target relation, if query is INSERT, UPDATE, or DELETE. * - * p_target_rangetblentry: target relation's entry in the rtable list. - * - * p_target_rtindex: target relation's index in the rtable list. + * p_target_nsitem: target relation's ParseNamespaceItem. * * p_is_insert: true to process assignment expressions like INSERT, false * to process them like UPDATE. (Note this can change intra-statement, for @@ -174,7 +175,7 @@ typedef Node *(*CoerceParamHook) (ParseState *pstate, Param *param, */ struct ParseState { - struct ParseState *parentParseState; /* stack link */ + ParseState *parentParseState; /* stack link */ const char *p_sourcetext; /* source text, or NULL if not available */ List *p_rtable; /* range table so far */ List *p_joinexprs; /* JoinExprs for RTE_JOIN p_rtable entries */ @@ -187,8 +188,7 @@ struct ParseState List *p_future_ctes; /* common table exprs not yet in namespace */ CommonTableExpr *p_parent_cte; /* this query's containing CTE */ Relation p_target_relation; /* INSERT/UPDATE/DELETE target rel */ - RangeTblEntry *p_target_rangetblentry; /* target rel's RTE, or NULL */ - int p_target_rtindex; /* target rel's RT index, or 0 */ + ParseNamespaceItem *p_target_nsitem; /* target rel's NSItem, or NULL */ bool p_is_insert; /* process assignment like INSERT not UPDATE */ List *p_windowdefs; /* raw representations of window clauses */ ParseExprKind p_expr_kind; /* what kind of expression we're parsing */ @@ -225,6 +225,9 @@ struct ParseState /* * An element of a namespace list. * + * The p_nscolumns array contains info showing how to construct Vars + * referencing corresponding elements of the RTE's colnames list. + * * Namespace items with p_rel_visible set define which RTEs are accessible by * qualified names, while those with p_cols_visible set define which RTEs are * accessible by unqualified names. These sets are different because a JOIN @@ -249,15 +252,49 @@ struct ParseState * are more complicated than "must have different alias names", so in practice * code searching a namespace list has to check for ambiguous references. */ -typedef struct ParseNamespaceItem +struct ParseNamespaceItem { RangeTblEntry *p_rte; /* The relation's rangetable entry */ int p_rtindex; /* The relation's index in the rangetable */ + /* array of same length as p_rte->eref->colnames: */ + ParseNamespaceColumn *p_nscolumns; /* per-column data */ bool p_rel_visible; /* Relation name is visible? */ bool p_cols_visible; /* Column names visible as unqualified refs? */ bool p_lateral_only; /* Is only visible to LATERAL expressions? */ bool p_lateral_ok; /* If so, does join type allow use? */ -} ParseNamespaceItem; +}; + +/* + * Data about one column of a ParseNamespaceItem. + * + * We track the info needed to construct a Var referencing the column + * (but only for user-defined columns; system column references and + * whole-row references are handled separately). + * + * p_varno and p_varattno identify the semantic referent, which is a + * base-relation column unless the reference is to a join USING column that + * isn't semantically equivalent to either join input column (because it is a + * FULL join or the input column requires a type coercion). In those cases + * p_varno and p_varattno refer to the JOIN RTE. + * + * p_varnosyn and p_varattnosyn are either identical to p_varno/p_varattno, + * or they specify the column's position in an aliased JOIN RTE that hides + * the semantic referent RTE's refname. (That could be either the JOIN RTE + * in which this ParseNamespaceColumn entry exists, or some lower join level.) + * + * If an RTE contains a dropped column, its ParseNamespaceColumn struct + * is all-zeroes. (Conventionally, test for p_varno == 0 to detect this.) + */ +struct ParseNamespaceColumn +{ + Index p_varno; /* rangetable index */ + AttrNumber p_varattno; /* attribute number of the column */ + Oid p_vartype; /* pg_type OID */ + int32 p_vartypmod; /* type modifier value */ + Oid p_varcollid; /* OID of collation, or InvalidOid */ + Index p_varnosyn; /* rangetable index of syntactic referent */ + AttrNumber p_varattnosyn; /* attribute number of syntactic referent */ +}; /* Support for parser_errposition_callback function */ typedef struct ParseCallbackState |