CREATE FUNCTION (SQL) CREATE FUNCTION (外部) 創建地點 CREATE MATERIALIZED VIEW CREATE RECIPIENT CREATE SCHEMA CREATE SERVER CREATE SHARE CREATE STREAMING TABLE CREATE TABLE 數據表屬性和數據表選項 CREATE TABLE 使用 Hive 格式 CREATE TABLE CONSTRAINT ...
and an error is returned. When a new PRIMARY KEY or UNIQUE constraint is added to an existing column, the data in the column or columns must be unique. If duplicate values are found, ALTER TABLE fails. The WITH NOCHECK option has no effect when PRIMARY KEY or UNIQUE constraints are ...
column_definition|[,|[CONSTRAINT[constraint_name]]{PRIMARYKEY|UNIQUE}(column_name)//在创建所有列后添加约束|[CONSTRAINT[constraint_name]]FOREIGNKEY(column_name,column_name...)references_clause constraint_state|[CONSTRAINT[constraint_name]]CHECK(expression)constraint_state]column_definition_list: column_...
The table declaration includes column definitions, names, data types, and constraints. The only constraint types allowed are PRIMARY KEY, UNIQUE KEY, and NULL. For more information about the syntax, see CREATE TABLE (Transact-SQL), CREATE FUNCTION (Transact-SQL), and DECLARE @local_variable (...
TRUNCATE TABLEremoves all rows from a table, but the table structure and its columns, constraints, indexes, and so on, remain. To remove the table definition in addition to its data, use theDROP TABLEstatement. If the table contains an identity column, the counter for that column is reset...
1cat /tmp/alterstatements.sql 3. Run the SQL file against the current database. 1mysql my_jira_db < /tmp/alterstatements.sql After running the query for all affected tables, verify that the queries below now return no results; 1SELECT*FROMinformation_schema.COLUMNSWHEREtable_sche...
ADD ( { column_name data_type [ compress_mode ] } [, ...] ) 向表中增加多列。 MODIFY [ COLUMN ] column_name data_type 修改表已存在字段的数据类型。需注意:不支持修改分布列数据类型。 MODIFY [ COLUMN ] column_name [ CONSTRAINT constraint_name ] NOT NULL [ ENABLE ] 为表的某列添加...
Check constraints or partition function of source table ALTER TABLE with variable TableName ALTER vs UPDATE when creating a new column with default value. Alternate queries for MERGE Alternative for OR in WHERE clause Alternative for PIVOT Alternative of CURSOR in SQL to improve performance ?
其中table_constraint为: [CONSTRAINT constraint_name] {PRIMARY KEY | UNIQUE} (column_name) [NOT ENFORCED [ENABLE QUERY OPTIMIZATION | DISABLE QUERY OPTIMIZATION] | ENFORCED] 参数说明 IF NOT EXISTS 如果已经存在相同名称的表,不会抛出一个错误,而会发出一个通知,告知表关系已存在。 table_name 外...
SqlDbType StateChangeEventArgs StateChangeEventHandler StatementCompletedEventArgs StatementCompletedEventHandler StatementType StrongTypingException SyntaxErrorException TypedTableBase<T> TypedTableBase<T> 构造函数 方法 显式接口实现 TypedTableBaseExtensions UniqueConstraint UpdateRowSource UpdateStatus VersionNotFoundExc...