diff options
| author | Bruce Momjian <bruce@momjian.us> | 2001-05-19 01:57:11 +0000 |
|---|---|---|
| committer | Bruce Momjian <bruce@momjian.us> | 2001-05-19 01:57:11 +0000 |
| commit | 385d271b813cf6b389677e7f4ce0bc55e51ddcf6 (patch) | |
| tree | 5ba760610ab2a1077e547b18ffe36d0222571aa3 /src/backend/parser/parse_func.c | |
| parent | 5e987038ceef535c72063ddb814a154f0c3c8e4c (diff) | |
| download | postgresql-385d271b813cf6b389677e7f4ce0bc55e51ddcf6.tar.gz postgresql-385d271b813cf6b389677e7f4ce0bc55e51ddcf6.zip | |
Comment additions in parser.
Diffstat (limited to 'src/backend/parser/parse_func.c')
| -rw-r--r-- | src/backend/parser/parse_func.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c index 4c24d684991..ef2adde5cc4 100644 --- a/src/backend/parser/parse_func.c +++ b/src/backend/parser/parse_func.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.107 2001/05/19 00:37:45 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/parser/parse_func.c,v 1.108 2001/05/19 01:57:11 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -106,6 +106,7 @@ ParseNestedFuncOrColumn(ParseState *pstate, Attr *attr, int precedence) /* * parse function + * * This code is confusing because the database can accept * relation.column, column.function, or relation.column.function. * In these cases, funcname is the last parameter, and fargs are @@ -115,6 +116,8 @@ ParseNestedFuncOrColumn(ParseState *pstate, Attr *attr, int precedence) * In this case, Funcname is the part before parens, and fargs * are the part in parens. * + * FYI, projection is choosing column from a table. + * */ Node * ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs, @@ -144,7 +147,8 @@ ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs, /* * Most of the rest of the parser just assumes that functions do * not have more than FUNC_MAX_ARGS parameters. We have to test - * here to protect against array overruns, etc. + * here to protect against array overruns, etc. Of course, this + * may not be a function, but the test doesn't hurt. */ if (nargs > FUNC_MAX_ARGS) elog(ERROR, "Cannot pass more than %d arguments to a function", @@ -158,6 +162,8 @@ ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs, } /* + * test for relation.column + * * check for projection methods: if function takes one argument, and * that argument is a relation, param, or PQ function returning a * complex * type, then the function could be a projection. @@ -170,9 +176,7 @@ ParseFuncOrColumn(ParseState *pstate, char *funcname, List *fargs, { Ident *ident = (Ident *) first_arg; - /* - * first arg is a relation. This could be a projection. - */ + /* First arg is a relation. This could be a projection. */ refname = ident->name; retval = qualifiedNameToVar(pstate, refname, funcname, true); |