EXEC sp_configure 'max server memory',14000 -- 设置最大内存为9G,我们server 内存是16G的,留下7G足够了 EXEC ('RECONFIGURE' ) GO EXEC sp_configure 'show advanced options', 0 --记得用完了把advanced options关掉 GO EXEC sp_configure N'max server memory (MB)', 200 DBCC FREEPROCCACHE DBCC FREE...
orderby e.HireDate select e) .Take(5); 1. 2. 3. 4. 5. 语句描述:选择所雇用的前5个雇员。 Skip 说明:跳过集合的前n个元素;延迟。即我们跳过给定的数目返回后面的结果集。 var q = ( from p in db.Products orderby p.UnitPrice descending select p) .Skip(10); 1. 2. 3. 4. 5. 语句...
当文件移动或修改时,由于用户建立的表和索引是建立在文件组上的,并不依赖具体文件,因此SQL Server可以放心的管理文件。 另外,使用文件组的方式来管理文件,可以使得同一文件组内的文件分布在不同的硬盘中,能够大大提供IO性能。 SQL Server根据每个文件设置的初始大小和增量值自动分配新加入的空间,假设在同一文件A设置的...
(descending)。在这种情况下,我们就可以运用 ORDER BY 这个指令来达到我们的目的。 ORDER BY 的语法如下: SELECT "栏位名" FROM "表格名" [WHERE "条件"] ORDER BY "栏位名" [ASC, DESC] (DESC 是descend 降序意思 asc 是ascend 升序的意思) [] 代表 WHERE子句不是一定需要的。不过,如果WHERE子句存在的...
This trace flag was introduced in SQL Server 2022 (16.x) and the behavior is enabled by default in SQL Server 2022 (16.x) CU 1. If you're using SQL Server 2022 (16.x) CU 1 and later versions, the trace flag is ignored. 818 Enables additional I/O diagnostics to check for Lost...
Specifies that the values in the specified column should be sorted in ascending or descending order. ASC is the default sort order. Null values are treated as the lowest possible values. ROWS or RANGE Applies to: SQL Server 2012 (11.x) and later versions. Further limits the rows within the...
每个SQL Server数据库至少包含两个作系统文件:一个数据文件(data file)和一个日志文件(log file)。数据文件包含数据和对象,例如表、索引、存储过程和视图...。日志文件包含恢复数据库所需的所有事务的相关数据。其实在SQL Server中,数据文件分为三类,分别为: 主...
SQL Server 2012 SP1 introduced a new type of XML index known as a Selective XML Index. This new index can improve querying performance over data stored as XML, allow for faster indexing of large XML data workloads, and improve scalability by reducing storage costs of the index itself. For...
(oper_type = '1' AND end_date <= add_months(trunc(sysdate, 'mm'), 1)) ORDER BY oper_time ASC ) c WHERE c.num <= : 1; 如果索引那两个系统参数是默认值,其中的full hint是可以去掉的。 当前使用的并行度是4,具体的并行度可以根据实际需要适当增减。
This trace flag was introduced in SQL Server 2022 (16.x) and the behavior is enabled by default in SQL Server 2022 (16.x) CU 1. If you're using SQL Server 2022 (16.x) CU 1 and later versions, the trace flag is ignored. 818 Enables additional I/O diagnostics to check for Lost ...