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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:
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Oracle Drop Column using DROP COLUMN clause. To drop a column from a table physically, you use the following statement: ALTER TABLE table_name DROP COLUMN column_name; Code language: SQL (Structured Query Language) (sql) To drop multiple columns, you use the statement below:
20 Δεκ 2012 · Use ALTER TABLE with DROP COLUMN to drop a column from a table, and CHANGE or MODIFY to change a column. ALTER TABLE tbl_Country DROP COLUMN IsDeleted; ALTER TABLE tbl_Country MODIFY IsDeleted tinyint(1) NOT NULL; ALTER TABLE tbl_Country CHANGE IsDeleted IsDeleted tinyint(1) NOT NULL;
This statement works in MySQL and PostgreSQL. For Oracle and SQL Server, you use the following statement: ALTER TABLE persons DROP COLUMN date_of_birth, phone; Code language: SQL (Structured Query Language) (sql) In this tutorial, you have learned how to use the SQL DROP COLUMN statement to remove one or more columns from a table.
To physically drop a column you can use one of the following syntaxes, depending on whether you wish to drop a single or multiple columns. alter table table_name drop column column_name; alter table table_name drop (column_name1, column_name2);
If you’d like to remove a column from a table, use this statement. First, write ALTER TABLE , followed by the name of the table you want to change (in our example, product ). Next add the DROP COLUMN clause, followed by the name of the column you want to remove (in our example, description ).
17 Οκτ 2009 · Step # 1: Login to mysql. Type the following command: mysql -u user -p databasename. Step 2: Delete column. First see table description: desc tableName. Use the following syntax at mysql> ALTER TABLE tableName DROP columnName; For example, see t1 table description, enter: DESC t1; Sample outputs:
