How do I drop a parent table in SQL?

How do I drop parent tables in SQL using cascade constraints?

In this statement:

  1. First, indicate the table and its schema that you want to drop after the DROP TABLE clause. …
  2. Second, specify CASCADE CONSTRAINTS clause to remove all referential integrity constraints which refer to primary and unique keys in the table.

How do I drop a table in SQL?

SQL Server DROP TABLE

  1. First, specify the name of the table to be removed.
  2. Second, specify the name of the database in which the table was created and the name of the schema to which the table belongs. The database name is optional. …
  3. Third, use IF EXISTS clause to remove the table only if it exists.

How do I drop a parent table in SQL Server?

In SQL Server, you cannot drop a table if it is referenced by a FOREIGN KEY constraint. You have to either drop the child tables before removing the parent table, or remove foreign key constraints.

Can we drop a parent table without deleting child table?

You can’t drop a parent table if you have a child table with a foreign key constraint in place, unless you specify the CASCADE CONSTRAINTS clause: DROP TABLE P CASCADE CONSTRAINTS; This command drops the FK constraint too.

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How do you drop a table that contains referential constraints?

To drop foreign key (referential) constraints, use the DROP CONSTRAINT clause of the ALTER TABLE statement. When a foreign key constraint is dropped, packages or cached dynamic statements containing the following might be marked as invalid: Statements that insert or update the table containing the foreign key.

What is the difference between DROP and DELETE table?

DELETE is a Data Manipulation Language command, DML command and is used to remove tuples/records from a relation/table. Whereas DROP is a Data Definition Language, DDL command and is used to remove named elements of schema like relations/table, constraints or entire schema.

Can we DROP a table or column which has primary key?

We can remove PRIMARY KEY constraint from a column of an existing table by using DROP keyword along with ALTER TABLE statement.

What does drop table do in SQL?

We use the SQL DROP Table command to drop a table from the database. It completely removes the table structure and associated indexes, statistics, permissions, triggers and constraints.

Which SQL keyword is used to retrieve a maximum value?

MAX() is the SQL keyword is used to retrieve the maximum value in the selected column.

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