SQL DROP INDEX Keyword
DROP INDEX The DROP INDEX command is used to delete an index in a table. MS Access: DROP INDEX index_name ON table_name; SQL Server: DROP INDEX table_name.index_name;
DROP INDEX The DROP INDEX command is used to delete an index in a table. MS Access: DROP INDEX index_name ON table_name; SQL Server: DROP INDEX table_name.index_name;
DROP DEFAULT The DROP DEFAULT command is used to delete a DEFAULT constraint. To drop a DEFAULT constraint, use the following SQL: SQL Server / Oracle / MS Access: ALTER TABLE Persons ALTER COLUMN City DROP DEFAULT;
DROP DATABASE The DROP DATABASE command is used to delete an existing SQL database. The following SQL drops a database named “testDB”: Example DROP DATABASE testDB; Note: Be careful before dropping a database. Deleting a database will result in loss…
DROP CONSTRAINT The DROP CONSTRAINT command is used to delete a UNIQUE, PRIMARY KEY, FOREIGN KEY, or CHECK constraint. DROP a UNIQUE Constraint To drop a UNIQUE constraint, use the following SQL : SQL Server / Oracle / MS Access:…
DROP COLUMN The DROP COLUMN command is used to delete a column in an existing table. The following SQL deletes the “ContactName” column from the “Customers” table: Example ALTER TABLE Customers DROP COLUMN ContactName;
DROP COLUMN The DROP COLUMN command is used to delete a column in an existing table. The following SQL deletes the “ContactName” column from the “Customers” table: Example ALTER TABLE Customers DROP COLUMN ContactName;
SELECT DISTINCT The SELECT DISTINCT command returns only distinct (different) values in the result set. The following SQL statement selects only the DISTINCT values from the “Country” column in the “Customers” table :
DESC The DESC command is used to sort the data returned in descending order. The following SQL statement selects all the columns from the “Customers” table, sorted descending by the “CustomerName” column :
DEFAULT The DEFAULT constraint provides a default value for a column. The default value will be added to all new records if no other value is specified. SQL DEFAULT on CREATE TABLE The following SQL sets a DEFAULT value for…