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opt_range.cc, range.result, range.test:

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Bug #6045: Binary Comparison regression in MySQL 4.1
  Binary searches didn't use a case insensitive index, now they do.
This commit is contained in:
bar@mysql.com
2004-11-03 15:22:33 +04:00
parent 4650f0acab
commit 45451568bf
3 changed files with 42 additions and 3 deletions
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15
sql/opt_range.cc
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@ -1013,13 +1013,22 @@ get_mm_leaf(PARAM *param, COND *conf_func, Field *field, KEY_PART *key_part,
}
/*
We can't use an index when comparing strings of
different collations
1. Usually we can't use an index if the column collation
differ from the operation collation.
2. However, we can reuse a case insensitive index for
the binary searches:
WHERE latin1_swedish_ci_column = 'a' COLLATE lati1_bin;
WHERE latin1_swedish_ci_colimn = BINARY 'a '
*/
if (field->result_type() == STRING_RESULT &&
value->result_type() == STRING_RESULT &&
key_part->image_type == Field::itRAW &&
((Field_str*)field)->charset() != conf_func->compare_collation())
((Field_str*)field)->charset() != conf_func->compare_collation() &&
!(conf_func->compare_collation()->state & MY_CS_BINSORT))
DBUG_RETURN(0);
if (type == Item_func::LIKE_FUNC)