百度试题 结果1 题目In SQL, the command to drop a table is ( ). A. remove table B. delete table C. clear table D. drop table 相关知识点: 试题来源: 解析 D 反馈 收藏
In this article, we will explore the process of SQL Delete column from an existing table. We will also understand the impact of removing a column with defined constraints and objects on it. 在本文中,我们将探讨从现有表中删除SQL列的过程。 我们还将理解删除具有定义的约束和对象的列的影响。 (Int...
A. It fails to delete the records because the records are locked in the SHARE mode B. It deletes the rows successfully because the table is locked in the SHARE mod C. It fails to delete the records because the table is locked in EXCLUSIVE mode D. ROP TABLE的过程在执行,该会话已经获得...
DROP TEMPORARY TABLE TEMP_TABLE; ExampleFollowing is an example to delete a temporary table CUSTOMERS.DROP TEMPORARY TABLE CUSTOMERS; Print Page Previous Next AdvertisementsTOP TUTORIALS Python Tutorial Java Tutorial C++ Tutorial C Programming Tutorial C# Tutorial PHP Tutorial R Tutorial HTML Tutorial CSS...
DELETE, DELETE - SQL uses record locking when marking multiple records for deletion in tables opened for shared access. This reduces record contention in multiuser situations, but may reduce performance. For maximum performance, open the table for exclusive use or use FLOCK( ) to lock the table...
DROP TABLE `content`, `content_admin`, `content_cat`, `content_cmt_post`; The above command will delete four tables. Dropping a unique constraints We can use DROP sql command to remove unique constraints associated to any column, here is an example. ...
SELECT tablespace_name FROM all_tables WHERE table_name = 'YOURTABLENAME'; 18 How to remove duplicate rows from a table If the unique/primary keys can be identified from the table, it is easier to remove the records from the table using the following query: DELETE FROM tablename WHERE row...
Visual FoxPro uses the default value if you use the ALTER TABLE - SQL command to remove autoincrementing for the field. PRIMARY KEY | UNIQUE PRIMARY KEY creates a primary index for the field specified in FieldName1. UNIQUE creates a candidate index for the field specified in FieldName1. ...
DELETE [Scope] [FOR lExpression1] [WHILE lExpression2] [IN nWorkArea | cTableAlias] [NOOPTIMIZE] Parameters Scope Specifies a range of records to mark for deletion. The scope clauses are: ALL, NEXTnRecords, RECORDnRecordNumber, and REST. ...
SqlConnection SqlConnectionStringBuilder SqlCredential SqlDataAdapter SqlDataAdapter 构造函数 属性 DeleteCommand InsertCommand SelectCommand UpdateBatchSize UpdateCommand 事件 显式接口实现 SqlDataReader SqlDependency SqlError SqlErrorCollection SqlException SqlInfoMessageEventArgs ...