For searches on text columns, with results sorted by relevance, see full-text indexes.This can help speed up some LIKE queries by providing the optimizer with more information about your data. If this is done, then the optimizer will read optimizer_selectivity_sampling_limit rows to calculate the selectivity of the LIKE expression before starting to calculate the query plan. Starting from MariaDB 10.0, one can set the optimizer_use_condition_selectivity variable to 5.MariaDB can use indexes for LIKE on string columns in the case where the LIKE doesn't start with % or _.You can include functions and operators in the expression to match. Use COLLATE to specify a binary collation, forcingĬase-sensitive matches: SELECT * FROM t1 WHERE d like "t%" COLLATE latin1_bin SELECT * FROM t1 WHERE d like "t%" COLLATE latin1_bin With the default collations, LIKE is case-insensitive: SELECT * FROM t1 where d like "t%" SELECT * FROM t1 where d like "t%" Select the six-character day names: SELECT * FROM t1 WHERE d like "_day" SELECT * FROM t1 WHERE d like "_day" Select the days that contain the substring "es": SELECT * FROM t1 WHERE d LIKE "%es%" SELECT * FROM t1 WHERE d LIKE "%es%" Select the days that begin with "T": CREATE TABLE t1 ( d VARCHAR ( 16 )) INSERT INTO t1 VALUES ( "Monday" ), ( "Tuesday" ), ( "Wednesday" ), ( "Thursday" ), ( "Friday" ), ( "Saturday" ), ( "Sunday" ) SELECT * FROM t1 WHERE d LIKE "T%" SELECT * FROM t1 WHERE d LIKE "T%" To avoid difficulties with the backslash character, you can change the wildcard escapeĬharacter using ESCAPE in a LIKE expression. Thus, to match anĪctual backslash, you sometimes need to double-escape it as "\ \ \ \". Parsed as well as to escape wildcards in a pattern after parsing. ![]() The backslash is used both to encode special characters like newlines when a string is You can prefix the wildcard characters the backslash character \ to escape them. ![]() If you need to match the characters _ or %, you must escape them. Use CONVERT to use the expression in a different character set. Will not match _latin1"€" because the Euro sign is not a valid latin1 character. For example, _ will match _utf8"€", but it If it is valid in the expression's character set. It will only match a multi-byte character The _ wildcard matches a single character, not byte. Numeric arguments are coerced to binary strings. Collations ending in _bin are case-sensitive. Use SHOW COLLATION to get a list ofĪvailable collations. ![]() To use a binary collation using COLLATE, or coerce either of them to a BINARY For case-sensitive matches, declare either argument LIKE performs case-insensitive substring matches if the collation for theĮxpression and pattern is case-insensitive. If either the expression or the pattern is NULL, the result is NULL. The NOT operator on the entire LIKE expression. Use NOT LIKE to test if a string does not match a pattern. % matches any number of characters, including zero.Patterns may use the following wildcard characters: Returns either 1 ( TRUE) or 0 ( FALSE).īoth expr and pat may be any valid expression and are evaluated to strings. Tests whether expr matches the pattern pat.
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