ADD [UNIQUE] [INDEX|KEY] index_name USING index_type(column_name[(length)]) [ASC|DESC]; 1. 2. 3. 与CREATE INDEX相比,ALTER TABLE语句在增加索引的同时还可以指定要增加索引的表名。 下面是一个使用ALTER TABLE语句增加B-tree索引的例子: ALTER TABLE ta
In this article, we explore the current options letting us add new columns to an existing table in SQL Server database. The use case may arise on many occasions. Particularly, it happens when there are updates for an application, and they demand adding new columns. Create a Table To begin...
( ValidTo ASC, ValidFrom ASC ) WITH ( PAD_INDEX = OFF, SORT_IN_TEMPDB = OFF, DROP_EXISTING = OFF, ONLINE = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON ) ON [PRIMARY]; /*(3) Create constraints matching the partition that will ...
如果SQL Server 版本不支援 Always On 可用性群組,請使用記錄傳送。資料庫鏡像267 索引選項sp_indexoptionALTER INDEXsp_indexoption78 索引選項CREATE TABLE、ALTER TABLE 或 CREATE INDEX 語法,但是選項周圍沒有括號。請重寫陳述式來使用目前的語法。索引選項33 ...
Most of you must have come across the pain of adding a not null column with a default value to an existing big table. It takes minutes to add columns. I recently found out that this problem has been resolved in SQL Server 2012. Let’s look into some ways to resolve this in versions...
SQL Server 性能调优3 之索引(Index)的维护 前言 前一篇的文章介绍了通过建立索引来提高数据库的查询性能,这其实只是个开始。后续如果缺少适当的维护,你先前建立的索引甚至会成为拖累,成为数据库性能的下降的帮凶。 查找碎片 消除碎片可能是索引维护最常规的任务,微软官方给出的建议是当碎片等级为 5% - 30% 之间时...
因此,事务日志必须具有足够的空间来存储索引操作事务和所有的并发用户事务,以满足索引操作过程的需要。 有关详细信息,请参阅Transaction Log Disk Space for Index Operations。 可恢复索引注意事项 创建索引和索引重新生成的可恢复索引选项适用于 SQL Server (从 SQL Server 2017 (14.x) 开始支持索引重新生成,SQL Se...
Applies to: SQL Server Azure SQL Database Azure SQL Managed Instance SQL database in Microsoft Fabric Creates a new table in the database. Note For reference to Warehouse in Microsoft Fabric, visit CREATE TABLE (Fabric Data Warehouse). For reference to Azure Synapse Analytics and Analytics ...
User must be a member of the sysadmin fixed server role or the db_ddladmin and db_owner fixed database roles. Use SQL Server Management Studio To move an existing index to a different filegroup using Table Designer In Object Explorer, click the plus sign to expand the database that ...
COUNT (SQL Server Compact) CREATE DATABASE (SQL Server Compact) CREATE INDEX (SQL Server Compact) CREATE STATISTICS (SQL Server Compact) CREATE TABLE (SQL Server Compact) DATALENGTH (SQL Server Compact) DATEADD (SQL Server Compact) DATEDIFF (SQL Server Compact) DATENAME (SQL Server Compact) DATE...