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This tutorial shows you how to use Oracle drop column statements to drop one or more columns from a table logically and physically.
- DROP TABLE
DROP TABLE brands; Code language: SQL (Structured Query...
- DROP TABLE
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:
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);
This Oracle tutorial explains how to use the Oracle ALTER TABLE statement to add a column, modify a column, drop a column, rename a column or rename a table (with syntax, examples and practice exercises).
28 Οκτ 2019 · 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; --drop SINGLE column. ALTER TABLE table_name DROP (column_name1, column_name2); --drop MANY columns. Source.
Oracle and SQL Server have a slightly different syntax: ALTER TABLE table_name. DROP COLUMN . column_name1, . [column_name2]; Code language: SQL (Structured Query Language) (sql) SQL DROP COLUMN examples. The following statement creates a new table named persons for the demonstration: CREATE TABLE persons ( person_id INT PRIMARY KEY,
2 Σεπ 2019 · To drop a column in an existing table in Oracle, here is the syntax: ALTER TABLE table_name. DROP COLUMN column_name; To drop multiple columns in an existing table: ALTER TABLE table_name . DROP (column_name1, column_name2,…); The DROP commands above are called physical delete.
