Search results
15 maj 2012 · Yes, we can create functional index in MySQL. This feature is available from MySQL 8.0.13. (Other RDBMS have this feature in its earlier releases But MySQL introduced it in its release 8.0.13).
A function-based index calculates the result of a function that involves one or more columns and stores that result in the index. The following shows the syntax of creating a function-based index: CREATE INDEX index_name ON table_name (expression); Code language: SQL (Structured Query Language) (sql)
12 sty 2023 · In this post we discuss how to create functional indexes as well as some limitations and implications with their use. First introduced to MySQL in version 8.013, functional indexes give us the ability to create indexes based on expressions rather than the values of data in a database column.
4 sie 2010 · You could emulate function based indexes if your database supports insert and update triggers. Add a column that will contain the function values and add index for that column. Then have your triggers to update column containing function values.
CREATE INDEX enables you to add indexes to existing tables. CREATE INDEX is mapped to an ALTER TABLE statement to create indexes. See Section 13.1.9, “ALTER TABLE Statement”. CREATE INDEX cannot be used to create a PRIMARY KEY; use ALTER TABLE instead.
The CREATE INDEX statement is used to create indexes in tables. Indexes are used to retrieve data from the database more quickly than otherwise. The users cannot see the indexes, they are just used to speed up searches/queries.
In this tutorial, you will learn how to use the Oracle CREATE INDEX statement to create a new index on one or more columns of a table.
