Creating Indexes
CREATE INDEX index_name
ON table_name(column_name);
Removing Indexes
DROP INDEX index_name;
Listing Indexes
SHOW INDEXES IN table_name;
Modifying Indexes
Modifying an existing index often means dropping the old index and creating a new one. PostgreSQL, MySQL, and MS SQL Server provide a way to re-index without dropping and recreating them manually.
REINDEX INDEX index_name;