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使用 Create type 创建自定义的Table Type ，Syntax 如下，和Create Table的 语法十分相似。
CREATE TYPE [ schema_name. ] type_name { FROM base_type [ ( precision [ , scale ] ) ] [ NULL | NOT NULL ] | AS TABLE ( { <column_definition> | <computed_column_definition> } [ <table_constraint> ] [ ,...n ] ) } [ ; ] <column_definition> ::= column_name <data_type> [ COLLATE collation_name ] [ NULL | NOT NULL ] [ DEFAULT constant_expression ] | [ IDENTITY [ ( seed ,increment ) ] ] [ ROWGUIDCOL ] [ <column_constraint> [ ...n ] ] <column_constraint> ::= { { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] [ WITH ( <index_option> [ ,...n ] ) ] | CHECK ( logical_expression ) } <table_constraint> ::= { { PRIMARY KEY | UNIQUE } [ CLUSTERED | NONCLUSTERED ] ( column_name [ ASC | DESC ] [ ,...n ] ) [ WITH ( <index_option> [ ,...n ] )] | CHECK ( logical_expression ) }
Examples
1，Creating an alias type based on the varchar data type
CREATE TYPE dbo.PhoneNum FROM varchar(11) NOT NULL ;
2,Creating a user-defined table type
/* Create a user-defined table type */ CREATE TYPE dbo.LocationTableType AS TABLE ( LocationID bigint not null primary key clustered, LocationName VARCHAR(50) not null, CostRate float check(CostRate between 0.0 and 1.0) ) GO
3,drop user-defined type
drop type dbo.LocationTableType
Remarks
The DROP TYPE statement will not execute when any of the following is true:
There are tables in the database that contain columns of the alias data type or the user-defined type. Information about alias or user-defined type columns can be obtained by querying the sys.columns or sys.column_type_usages catalog views.
There are computed columns, CHECK constraints, schema-bound views, and schema-bound functions whose definitions reference the alias or user-defined type. Information about these references can be obtained by querying the sys.sql_expression_dependencies catalog view.
There are functions, stored procedures, or triggers created in the database, and these routines use variables and parameters of the alias or user-defined type. Information about alias or user-defined type parameters can be obtained by querying the sys.parameters or sys.parameter_type_usages catalog views.
参考doc：
Create User-Defined Table Type
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原文地址：http://www.cnblogs.com/ljhdo/p/5587095.html
