Search results
23 wrz 2009 · old_index_name must be the name of an existing index in the table that is not dropped by the same ALTER TABLE statement. new_index_name is the new index name, which cannot duplicate the name of an index in the resulting table after changes have been applied.
ALTER TABLE changes the structure of a table. For example, you can add or delete columns, create or destroy indexes, change the type of existing columns, or rename columns or the table itself. You can also change characteristics such as the storage engine used for the table or the table comment.
MySQL supports no syntax in ALTER TABLE to rename an index (or key, which is a synonym). You can ALTER TABLE DROP KEY and ALTER TABLE ADD KEY. There is no ALTER INDEX command in MySQL. You can only DROP INDEX and then CREATE INDEX with the new name.
26 sty 2024 · In this tutorial, we will delve into the art of managing indices on a MySQL 8 table. Understanding how to add, remove, and modify indices can significantly impact how quickly your application can retrieve data.
create index your_index_name on your_table_name(your_column_name) using HASH; or create index your_index_name on your_table_name(your_column_name) using BTREE;
The RENAME keyword is used to rename columns, indexes, and tables. include: RENAME COLUMN old_col_name TO new_col_name : Rename a column. RENAME INDEX old_index_name TO new_index_name : Rename a index.
The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. The ALTER TABLE statement is also used to add and drop various constraints on an existing table. ALTER TABLE - ADD Column
