![]() ![]() Insert into categories_case_sensitive(CategoryID,CategoryName) values(1, 'Beverages') `CategoryName` varchar(15) COLLATE utf8mb4_bin NOT NULL DEFAULT '' Use the COLLATE operator to define a column as case-sensitiveīelow a new table is created and column CategoryName is defined by COLLATE utf8mb4_bin which is case-sensitive. Index is not used EXPLAIN select * from categoriesĢ. Index is getting used EXPLAIN select * from categories To see the effect of index usage, run EXPLAIN command on the two queries. Applying BINARY to the value to be searched select * from categories ![]() Below the BINARY operator is applied to string 'Seafood' and index Uidx_categories_category_name is used. When applying BINARY to the value, the index of the column is used. ![]() Applying BINARY to column CategoryName select * from categories This forces the query engine to carry out row-by-row scan of the entire table. Has to be converted before comparing to the value 'Seafood'. This is because category name in each row When applying BINARY to a column, the index of the column becomes obsolete, which could dramatically slow down your query. In a query, it has performance differences when applying BINARY to a column versus applying BINARY to the value the column is searched for.The BINARY operator is deprecated as of MySQL 8.0.27, and you should expect its removal in a future version of MySQL.For example, in this queryīINARY is used with brackets like a function. You can treat the use of BINARY operator as a function like BINARY().Returns 0 which is FALSE because the string on the right-hand side of the equal sign has a trailing space. The BINARY operator also causes trailing spaces in comparisons to be significant.Note that category 'Seafood' is not in the result because the first letter 'S' is uppercase.īelow is the case-insensitive version of the above query and it extracts all category records where the category name contains character 's' or 'S' (both lowercase 's' and uppercase 'S' are returned in the result).Ī couple of things to note about using BINARY operator: It extracts all category records where the category name contains lowercase character 's'. The following query is case-sensitive search against a column by using BINARY operator. Query above returns 1 which is TRUE, whereas select 'géek' = BINARY 'geek' returns 0 which is FALSE. It forces a character string comparison to be done byte by byte using numeric byte values rather than character by character.įor example, the following query returns 1 which stands for TRUE because the string geek is the same as string GEEK.īut if we apply BINARY operator to the string 'GEEK', the result is FALSE (returns 0) because the string lowercase geek is different to uppercase string GEEK. The BINARY operator converts a character string to a binary string. String comparison is NOT case-sensitive by default in MySQL, but if there is a need for case-sensitive string comparison, there are ways to deal with it. How to make case-sensitive comparison in MySQL ![]()
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