So you also might change the type of user_name, or with V3.23. See chapter "7.3.7 Cast operators" of the MySQL Reference Manual. If no cases are found TRUE, and the statement does not have an ELSE part or value, then the CASE returns NULL. Starting with V3.23.0 it's also possible to force a comparison into case sensitivity with the cast operator BINARY, independent of the types of involved fields. CASE in MySQL is a type of control statement which validates the set of conditional cases and displays the value when the first case is meeting otherwise else value and exits the loop. See chapter "7.2.7 String types" of the MySQL Reference Manual and look for the statements on sorting and comparisons. If you compare a field from (a) with a field from (b), then the comparison will be case sensitive (case sensitivity wins). CASE statements in the ORDER BY clause are used to change the output order and instruct the query to sort the results based on a certain requirement. The behaviour depends on the fields that are involved:Īnd all variants of TEXT fields do compare case insensitive.Īnd all variants of BLOB fields do compare case sensitive. The pattern matching with regular expression ( RLIKE or REGEXP) isĪlways case sensitive for all versions of MySQL except the newestįor example: SELECT phone FROM user WHERE user_name REGEXP 'term' įor both the normal comparison (=) and the SQL pattern matching ( LIKE) Use any of the functions LOCATE, POSITION, or INSTR.įor example: SELECT phone FROM user WHERE POSITION('term' IN user_name)>0 ( CASE WHEN menuitems.parent '0' THEN menuitems.parent ELSE (SELECT mi.name FROM menuitems mi WHERE mi.id menuitems.parent) END ) AS ParentID. The string functions in MySQL are always case sensitive, so you could You always should state with your question which version of MySQL you're using, because MySQL is in steady development. For example, in the case- sensitive database, I can do select * from casetable where thing collate latin1_swedish_ci = "abc" Note that you can also change the collation from within a query. While in a case-insensitive database, we get: select thing, count(*) from casetable group by thing FROM tablename WHERE condition Note: The WHERE clause is not only used in SELECT statements, it is also used in UPDATE, DELETE, etc. Select * from casetable where thing = "abc" In a case-sensitive database, we get: select thing, count(*) from casetable group by thing This has an effect on things like grouping and equality. You can choose a case-sensitive collation, for example latin1_general_cs ( MySQL grammar): CREATE SCHEMA IF NOT EXISTS `myschema` The default collation for character set latin1, which is latin1_swedish_ci, happens to be case-insensitive. Each character set has a default collation see here for more information. Whenever you create database in MySQL, the database/schema has a character set and a collation. Although SQL case statements are most commonly seen in the SELECT part of queries, there is nothing stopping us from using it in the where clause. By default, MySQL does not consider the case of the strings
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