![]() ![]() How to use MySQL REPLACE function in SELECT and UPDATE queriesĬopyright © 2023. MySQL POSITION() function with examplesĢ3. Use GREATEST function to find the LARGEST value from multiple argumentsĢ0. Use LEAST function to find the SMALLEST value from multiple argumentsġ8. Using LIMIT, SQL_CALC_FOUND_ROWS and FOUND_ROWS() to Page Thru Query Result in MySQLġ7. Using LIMIT and OFFSET to Page Thru Query Result in MySQLġ6. Compare RANK(), DENSE_RANK(), and ROW_NUMBER() functionġ5. Using MySQL Date and Time Functions, Part 3ġ4. Using MySQL Date and Time Functions, Part 2Ħ. Using MySQL Date and Time Functions, Part 1ĥ. Query the new table as normal (BINARY operator is not needed and the search on CategoryName column is case-sensitive by default).Ĥ. Insert into categories_case_sensitive(CategoryID,CategoryName) values(8, 'Seafood') Insert into categories_case_sensitive(CategoryID,CategoryName) values(7, 'Produce') Insert into categories_case_sensitive(CategoryID,CategoryName) values(6, 'Meat/Poultry') Insert into categories_case_sensitive(CategoryID,CategoryName) values(5, 'Grains/Cereals') Insert into categories_case_sensitive(CategoryID,CategoryName) values(4, 'Dairyé Products') Insert into categories_case_sensitive(CategoryID,CategoryName) values(3, 'Confections') Insert into categories_case_sensitive(CategoryID,CategoryName) values(2, 'Condiments') 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. ![]()
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