sql query to get count of records

Original address: http://www.cnblogs.com/lyhabc/p/3367274.htmlBefore reading this article, you can read the following article firstSQL Server's unique task scheduling algorithm "Sqlos"Task Scheduler for SQL Server Sqlos [go]Translated

Read SQL Server query planRead Catalogue Begin How SQL Server looks for records SQL Server Join method More specific execution procedures Index statistics: The choice of the query plan is based on Optimizing View Queries

Problem description In the production database, the data of one table is 1 billion level, and that of the other table is 10 billion level. The data of other tables is also quite large. I didn't know that these tables had such a large amount of data

Read Catalogue Begin How SQL Server looks for records SQL Server Join method More specific execution procedures Index statistics: The choice of the query plan is based on Optimizing View Queries Recommended

The SQL statement used to query multiple fields, query multiple tables, and delete duplicate records. SQL repeat record Query 1. Search for redundant duplicate records in the Table. duplicate records are determined based on a single field (peopleId )

SQL Duplicate record query 1, look for redundant records in the table, duplicate records are based on a single field (Peopleid) to judge SELECT * from people where Peopleid to (select Peopleid from People GROUP by Peopleid have count

For more information about bugs fixed in SQL Server 2000 Service Pack 4, click the following article number to view the article in the Microsoft Knowledge Base:314128 FIX: When an RPC call is performed, Access with conflicting values includes an

First, the practical, the misunderstanding of the use of the indexThe purpose of the theory is to apply. Although we have just listed when clustered or nonclustered indexes should be used, in practice the above rules are easily overlooked or cannot

Optimizing queries can be a common thing for SQL Server optimizations. Since the optimization of database is a wide topic in itself, this article only talks about how to understand SQL Server query plan when optimizing query. After all, my knowledge

Today to see a Bo Friends of the article, feel good, reprint, hope to help you, more articles, please visit: http://blog.haoitsoft.com1, no index or no index (this is the most common problem of slow query, is the defect of program design)2, I/O