diff options
Diffstat (limited to 'src/include/nodes/parsenodes.h')
| -rw-r--r-- | src/include/nodes/parsenodes.h | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index f67bd9fad59..cdfa0568f7d 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1020,14 +1020,35 @@ typedef struct RangeTblEntry * be a Var of one of the join's input relations, or such a Var with an * implicit coercion to the join's output column type, or a COALESCE * expression containing the two input column Vars (possibly coerced). - * Within a Query loaded from a stored rule, it is also possible for + * Elements beyond the first joinmergedcols entries are always just Vars, + * and are never referenced from elsewhere in the query (that is, join + * alias Vars are generated only for merged columns). We keep these + * entries only because they're needed in expandRTE() and similar code. + * + * Within a Query loaded from a stored rule, it is possible for non-merged * joinaliasvars items to be null pointers, which are placeholders for * (necessarily unreferenced) columns dropped since the rule was made. * Also, once planning begins, joinaliasvars items can be almost anything, * as a result of subquery-flattening substitutions. + * + * joinleftcols is an integer list of physical column numbers of the left + * join input rel that are included in the join; likewise joinrighttcols + * for the right join input rel. (Which rels those are can be determined + * from the associated JoinExpr.) If the join is USING/NATURAL, then the + * first joinmergedcols entries in each list identify the merged columns. + * The merged columns come first in the join output, then remaining + * columns of the left input, then remaining columns of the right. + * + * Note that input columns could have been dropped after creation of a + * stored rule, if they are not referenced in the query (in particular, + * merged columns could not be dropped); this is not accounted for in + * joinleftcols/joinrighttcols. */ JoinType jointype; /* type of join */ + int joinmergedcols; /* number of merged (JOIN USING) columns */ List *joinaliasvars; /* list of alias-var expansions */ + List *joinleftcols; /* left-side input column numbers */ + List *joinrightcols; /* right-side input column numbers */ /* * Fields valid for a function RTE (else NIL/zero): @@ -3313,8 +3334,8 @@ typedef struct ConstraintsSetStmt */ /* Reindex options */ -#define REINDEXOPT_VERBOSE (1 << 0) /* print progress info */ -#define REINDEXOPT_REPORT_PROGRESS (1 << 1) /* report pgstat progress */ +#define REINDEXOPT_VERBOSE (1 << 0) /* print progress info */ +#define REINDEXOPT_REPORT_PROGRESS (1 << 1) /* report pgstat progress */ typedef enum ReindexObjectType { |