The DROP INDEX command is used to delete an index in a table. Sometimes it’s better to drop the indexes when there is not much performance gain for your table with indexes. To create a unique index by using the Table Designer. Hi Tom, I'm dropping unique constraint from a table and need to drop the unique index too. In SQL Server DROP INDEX Removes one or more relational, spatial, filtered, or XML indexes from the current database. A primary key or unique key index cannot be explicitly dropped. DROP INDEX. Db2 will automatically remove the associated index. Look at the below scenario, here no export import is involved, but in first case index is not dropped automatically: SQL> create unique index pk_emp1 on emp1(empno) ; Index …

Yes there's lot written about this topic and what is not … Now the table is created, we can drop the constraint using the below statement. If the primary index or unique key index was created automatically by the primary key constraint or unique constraint, to drop this kind of index, you use the ALTER TABLE statement to remove the primary key or unique constraint. Only one index name can be specified, and the CASCADE option is not supported.

In Object Explorer, expand the database that contains the table on which you want to create a unique index. If you created the index explicitly with the CREATE INDEX statement, then you can drop the index with the DROP INDEX statement. A unique index may consist of one or many columns. 1) Using DROP INDEX statement to delete an index. To drop a text index, specify the index name. When you drop an index, Oracle Database invalidates all objects that depend on the underlying table, including views, packages, package bodies, functions, and procedures. ORA-02429: cannot drop index used for enforcement of unique/primary key That shows a) unique did not create an index b) unique does not need a unique index ... it says what you mean We can use either a unique OR non-unique index to support a unique constraint. The syntax for both the statements is as follows − Syntax DROP INDEX index_name ON table_name; OR ALTER TABLE table_name DROP INDEX index_name; Example. For more information, see Create Indexes with Included Columns. Constraints are metadata, more metadata is … A primary key or unique key index cannot be explicitly dropped. Since in case of import, the two thiings happen separately, dropping the primary key now will NOT drop the index. If your indexes … Suppose we have the table ‘empl’ which have a UNIQUE constraint on column ‘empno’.