diff options
Diffstat (limited to 'src/include/nodes/primnodes.h')
| -rw-r--r-- | src/include/nodes/primnodes.h | 17 |
1 files changed, 15 insertions, 2 deletions
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h index 3ed4d74ee35..5abdbd548fd 100644 --- a/src/include/nodes/primnodes.h +++ b/src/include/nodes/primnodes.h @@ -10,7 +10,7 @@ * Portions Copyright (c) 1996-2003, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * - * $PostgreSQL: pgsql/src/include/nodes/primnodes.h,v 1.100 2004/06/09 19:08:18 tgl Exp $ + * $PostgreSQL: pgsql/src/include/nodes/primnodes.h,v 1.101 2004/08/17 18:47:09 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -97,13 +97,16 @@ typedef struct Resdom * Alias - * specifies an alias for a range variable; the alias might also * specify renaming of columns within the table. + * + * Note: colnames is a list of Value nodes (always strings). In an RTE's + * eref Alias, the colnames list includes dropped columns, so that the + * colname list position matches the physical attribute number. */ typedef struct Alias { NodeTag type; char *aliasname; /* aliased rel name (never qualified) */ List *colnames; /* optional list of column aliases */ - /* Note: colnames is a list of Value nodes (always strings) */ } Alias; typedef enum InhOption @@ -663,6 +666,16 @@ typedef struct ArrayExpr /* * RowExpr - a ROW() expression + * + * Note: the list of fields must have a one-for-one correspondence with + * physical fields of the associated rowtype, although it is okay for it + * to be shorter than the rowtype. That is, the N'th list element must + * match up with the N'th physical field. When the N'th physical field + * is a dropped column (attisdropped) then the N'th list element can just + * be a NULL constant. (This case can only occur for named composite types, + * not RECORD types, since those are built from the RowExpr itself rather + * than vice versa.) It is important not to assume that length(args) is + * the same as the number of columns logically present in the rowtype. */ typedef struct RowExpr { |