diff options
Diffstat (limited to 'src/backend/utils/adt/like_support.c')
| -rw-r--r-- | src/backend/utils/adt/like_support.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/src/backend/utils/adt/like_support.c b/src/backend/utils/adt/like_support.c index 69509811ef7..a65e63736c4 100644 --- a/src/backend/utils/adt/like_support.c +++ b/src/backend/utils/adt/like_support.c @@ -258,6 +258,20 @@ match_pattern_prefix(Node *leftop, patt = (Const *) rightop; /* + * Not supported if the expression collation is nondeterministic. The + * optimized equality or prefix tests use bytewise comparisons, which is + * not consistent with nondeterministic collations. The actual + * pattern-matching implementation functions will later error out that + * pattern-matching is not supported with nondeterministic collations. + * (We could also error out here, but by doing it later we get more + * precise error messages.) (It should be possible to support at least + * Pattern_Prefix_Exact, but no point as along as the actual + * pattern-matching implementations don't support it.) + */ + if (!get_collation_isdeterministic(expr_coll)) + return NIL; + + /* * Try to extract a fixed prefix from the pattern. */ pstatus = pattern_fixed_prefix(patt, ptype, expr_coll, |