diff options
| -rw-r--r-- | src/backend/parser/gram.y | 18 |
1 files changed, 14 insertions, 4 deletions
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index 4440cf351a7..5c9f33daf31 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -11,7 +11,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.511 2005/09/23 22:25:25 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/parser/gram.y,v 2.512 2005/11/13 19:11:28 tgl Exp $ * * HISTORY * AUTHOR DATE MAJOR EVENT @@ -7579,9 +7579,10 @@ position_list: * SQL9x defines a specific syntax for arguments to SUBSTRING(): * o substring(text from int for int) * o substring(text from int) get entire string from starting point "int" - * o substring(text from pattern) get entire string matching pattern * o substring(text for int) get first "int" characters of string - * We also want to implement generic substring functions which accept + * o substring(text from pattern) get entire string matching pattern + * o substring(text from pattern for escape) same with specified escape char + * We also want to support generic substring functions which accept * the usual generic list of arguments. So we will accept both styles * here, and convert the SQL9x style to the generic list for further * processing. - thomas 2000-11-28 @@ -7593,6 +7594,7 @@ substr_list: } | a_expr substr_for substr_from { + /* not legal per SQL99, but might as well allow it */ $$ = list_make3($1, $3, $2); } | a_expr substr_from @@ -7601,10 +7603,18 @@ substr_list: } | a_expr substr_for { + /* + * Since there are no cases where this syntax allows + * a textual FOR value, we forcibly cast the argument + * to int4. This is a kluge to avoid surprising results + * when the argument is, say, int8. It'd be better if + * there were not an implicit cast from int8 to text ... + */ A_Const *n = makeNode(A_Const); n->val.type = T_Integer; n->val.val.ival = 1; - $$ = list_make3($1, (Node *)n, $2); + $$ = list_make3($1, (Node *) n, + makeTypeCast($2, SystemTypeName("int4"))); } | expr_list { |