diff options
Diffstat (limited to 'src/backend/utils/adt/varlena.c')
| -rw-r--r-- | src/backend/utils/adt/varlena.c | 145 |
1 files changed, 144 insertions, 1 deletions
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c index 2a5f97ff028..6be21d241f1 100644 --- a/src/backend/utils/adt/varlena.c +++ b/src/backend/utils/adt/varlena.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.97 2003/05/09 15:44:40 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.98 2003/05/15 15:50:19 petere Exp $ * *------------------------------------------------------------------------- */ @@ -1050,6 +1050,149 @@ text_smaller(PG_FUNCTION_ARGS) PG_RETURN_TEXT_P(result); } + +/* + * The following operators support character-by-character comparison + * of text data types, to allow building indexes suitable for LIKE + * clauses. + */ + +static int +internal_text_pattern_compare(text *arg1, text *arg2) +{ + int result; + + result = memcmp(VARDATA(arg1), VARDATA(arg2), + Min(VARSIZE(arg1), VARSIZE(arg2)) - VARHDRSZ); + if (result != 0) + return result; + else if (VARSIZE(arg1) < VARSIZE(arg2)) + return -1; + else if (VARSIZE(arg1) > VARSIZE(arg2)) + return 1; + else + return 0; +} + + +Datum +text_pattern_lt(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result < 0); +} + + +Datum +text_pattern_le(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result <= 0); +} + + +Datum +text_pattern_eq(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + if (VARSIZE(arg1) != VARSIZE(arg2)) + result = 1; + else + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result == 0); +} + + +Datum +text_pattern_ge(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result >= 0); +} + + +Datum +text_pattern_gt(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result > 0); +} + + +Datum +text_pattern_ne(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + if (VARSIZE(arg1) != VARSIZE(arg2)) + result = 1; + else + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_BOOL(result != 0); +} + + +Datum +bttext_pattern_cmp(PG_FUNCTION_ARGS) +{ + text *arg1 = PG_GETARG_TEXT_P(0); + text *arg2 = PG_GETARG_TEXT_P(1); + int result; + + result = internal_text_pattern_compare(arg1, arg2); + + PG_FREE_IF_COPY(arg1, 0); + PG_FREE_IF_COPY(arg2, 1); + + PG_RETURN_INT32(result); +} + + /*------------------------------------------------------------- * byteaoctetlen * |