2 DROP PRIMARY KEY CASCADE; --删除后可以看到不存在tb_dept主键约束及tb_cons2外键的记录 SQL> SELECT constraint_name,constraint_type,table_name,status,deferrable,validated 2 FROM user_constraints 3 ORDER BY table_name; CONSTRAINT_NAME C TABLE_NAME STATUS DEFERRABLE VALIDATED --- - --- --- --...
2 DROP PRIMARY KEY CASCADE; --删除后能够看到不存在tb_dept主键约束及tb_cons2外键的记录 SQL> SELECT constraint_name,constraint_type,table_name,status,deferrable,validated 2 FROM user_constraints 3 ORDER BY table_name; CONSTRAINT_NAME C TABLE_NAME STATUS DEFERRABLE VALIDATED --- - --- --- --...
The SQL DROP TABLE statement is a Data Definition Language (DDL) command that is used to remove a table's definition, and its data, indexes, triggers, constraints and permission specifications (if any).Note − You should be very careful while using this command because once a table is ...
SQL_CREATE_TABLE SQL_CREATE_TRANSLATION SQL_CURSOR_SENSITIVITY SQL_DDL_INDEX SQL_DESCRIBE_PARAMETER SQL_DM_VER SQL_DRIVER_AWARE_POOLING_SUPPORTED SQL_DRIVER_HDESC SQL_DROP_ASSERTION SQL_DROP_CHARACTER_SET SQL_DROP_COLLATION SQL_DROP_DOMAIN SQL_DROP_SCHEMA SQL_DROP_TABLE SQL_DROP_TRANSLATION SQL_...
Drop all constraints in Database DROP ALL USERS FROM DATABASE Drop and Create Constraint on Very Large Table Drop and recreate table in stored procedure Drop Database Error Msg 3701, Level 11, State 1, Line 1 Drop or Truncate a particular partition. DROP Table - How to force a delete of...
DROPTable[dbname][Schemaname]table1,table2….tablen; While the DROP command eliminates designated schema pieces like relations, tables, constraints, or the entire schema. The DELETE command removes a few or all tuples/records from a relation/table. Only those tuples that meet the WHERE clause...
CONSTRAINTS JOIN SUM CONTINUE KEY SYSTEM_USER CONVERT LANGUAGE TABLE CORRESPONDING LAST TEMPORARY COUNT LEADING THEN CREATE LEFT TIME CROSS LEVEL TIMESTAMP CURRENT LIKE TIMEZONE_HOUR CURRENT_DATE LOCAL TIMEZONE_MINUTE CURRENT_TIME LOWER TO CURRENT_TIMESTAMP ...
ALTER TABLE [dbo].[Products] DROP COLUMN [ProductFeedback], [ProductLaunchDate] GO 1. 2. 3. 4. (SQL DELETE column contains CHECK constraints) We use CHECK constraints to limit the value range in a column. Suppose you have a column having CHECK constrains on it. ...
ALL_SPARSE_COLUMNS <table_constraint> ::= [ CONSTRAINT constraint_name ] { { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] ( column_name [ ASC | DESC ] [ ,... n ] ) [ WITH FILLFACTOR = fillfactor | WITH ( <index_option> [ ,... n ] ) ] [ ON { partition_scheme_...
DROP TABLE - 删除表 CREATE INDEX - 创建索引(搜索键) DROP INDEX - 删除索引 SQL SELECT 语句:用于从数据库中选取数据。 SELECT column_name,column_name FROM table_name; SELECT * FROM table_name; SELECT DISTINCT 语句:用于返回唯一不同的值,即去掉重复值。 SELECT DISTINCTcolumn_name,column_name FROM...