astypelengthfromsys.columns a leftjoinsys.types bona.system_type_id=b.system_type_id and a.user_type_id=b.user_type_idwherea.object_id =(selectobject_idfromsys.objectswherename ='Address')
FROM{<table_source>[ , ...n ] }<table_source>::={ [database_name. [schema_name] . |schema_name. ]table_or_view_name[AS]table_or_view_alias|derived_table[AS]table_alias[ (column_alias[ , ...n ] ) ] |<joined_table>}<joined_table>::={<table_source><join_type><table_sour...
select dbid, name AS DB_NAME from master..sysdatabases where sid <> 0x01 14:查询某一个表的字段和数据类型 select column_name,data_type from information_schema.columns where table_name = '表名' [n].[标题]: Select * From TableName Order By CustomerName [n].[标题]: 来自http://dev.cs...
In SQL Server, all table constraints are database objects, just like tables, views, stored procedures, functions, and so on. Therefore, constraints must have unique names across the database. But because every table constraint is scoped to an individual table, it makes sense to adopt a naming...
Functions: fn_get_sql, fn_virtualfilestats, fn_virtualservernodes. Instance configuration: Syntax related to server memory, worker threads, CPU affinity, trace flags. Use service tiers and compute sizes instead. KILL STATS JOB. OPENQUERY, OPENDATASOURCE, and four-part names. .NET Framework: commo...
FROM Person.Contact WHERE LastName LIKE '[A-M]%sen' 在这个T-SQL语句中,查找以“A”到“M”之间的字符开头而以“sen”结尾的所有LastNames。其它标识一组特定字符的通配符语法也可以调用一个索引扫描操作来解决一个通配符搜索标准。 只在你需要的情况下使用DISTINCT ...
derived_table 可以使用 Transact-SQL 資料表值建構函式功能來指定多個資料列。 例如: SELECT * FROM (VALUES (1, 2), (3, 4), (5, 6), (7, 8), (9, 10) ) AS MyTable(a, b);。 如需詳細資訊,請參閱資料表值建構函式 (Transact-SQL)。 column_alias 取代衍生資料表結果集中資料行名稱的...
,ColumnName ,ColumnDataType ,ColumnLength ,OrdinalPosition ) SELECT @tableName ,ColumnName ,ColumnDataType ,ColumnLength ,Position FROM @resultSet; The New Solution The new solution consists of a permanent table that contains the information, per data type to do the conversion. That allows a jo...
These two queries are functionally equivalent (because in this case there is a unique key on the BusinessEntityId column) and return the same set of results. As you can see the Person table is just accessed once in the revised query. The cost of the re-written query is also ~ 6 times...
For example, a table named OrderData is a different table from a table named ORDERDATA. If the Database Engine is installed as non-case sensitive, those two table names are considered to be the same table, and that name can only be used one time....