We can also drop (remove) columns in a table using theALTER TABLEcommand with theDROPclause. For example, -- delete country column from Customers tableALTERTABLECustomersDROPCOLUMNcountry; Run Code Here, the SQL command removes thecountrycolumn from theCustomerstable. Rename a Table We can change...
ALTERTABLEtable_name DROPCOLUMNcolumn_name; The following SQL deletes the "Email" column from the "Customers" table: Example ALTERTABLECustomers DROPCOLUMNEmail; ALTER TABLE - RENAME COLUMN To rename a column in a table, use the following syntax: ...
ALTER TABLE では、列と制約を変更、追加、または削除して、テーブルの定義を変更します。 また、ALTER TABLE では、パーティションを再割り当ておよび再構築したり、制約とトリガーを無効化および有効化したりもします。
If you are not the owner of the table, you need the DROP ANY TABLE privilege in order to use the drop_table_partition or truncate_table_partition clause. You must also have space quota in the tablespace in which space is to be acquired in order to use the add_table_partition, modify_...
The following example sets the default value of thecreated_datecolumn to the current timestamp: ALTERTABLEordersALTERCOLUMNcreated_dateSETDEFAULTCURRENT_TIMESTAMP;Code language:SQL (Structured Query Language)(sql) In this tutorial, you’ve learned how to use the Db2ALTER TABLE ALTER COLUMNstatement ...
For Example: ALTER TABLE supplier MODIFY supplier_name varchar2(100) not null; This will modify the column calledsupplier_nameto be a data type of varchar2(100) and force the column to not allow null values. Syntax #2 To modify multiple columns in an existing table, the ALTER TABLE synta...
table_or_view_name 与该索引关联的表或视图的名称。 若要查看表或视图的索引详细信息,请使用 sys.indexes 目录视图。 当<database_name> 是当前数据库名称时,Azure SQL 数据库支持由三部分构成的名称 <database_name>.<schema_name>.<object_name> 格式,或者 <database_name>tempdb,<object_name> 以# 或...
SQL Server Azure SQL Database Azure SQL Managed Instance SQL database in Microsoft Fabric Specifies a set of options that can be applied to an index that is part of a constraint definition that is created by usingALTER TABLE. For a complete description of index options, seeCREATE INDEX. ...
A SQL Server 2005 system data type. An alias data type based on a SQL Server system data type. Alias data types are created with the CREATE TYPE statement before they can be used in a table definition. A .NET Framework user-defined type, and the schema to which it belongs. .NET Frame...
FL 500Installation SYSOPR authority (when the current SQLID of the process is set to SYSINSTL) To alter a system-period temporal table when one or more of the changes also result in changes to the associated history table, the privileges that are held by the authorization ID of the stateme...