SQL Server

--First day of the month:Select DATEADD (Dd,-day (getdate ()) +1,getdate ())--Last day of the month:SELECT DateAdd (Ms,-3,dateadd (mm, DATEDIFF (M,0,getdate ()) +1, 0))--First day of last month: select CONVERT (int, CONVERT (varchar), DATEADD (M,-1,

With the widespread popularization of Internet application, the storage and access of massive data has become the bottleneck problem of system design. For a large-scale Internet application, every day millions even hundreds of millions of PV

SmallInt is an accurate numeric data type whose accuracy is unchanged after arithmetic operations, with 2-byte encodingThe range of signed smallint values is -2^15-------2^15-1, which is -32768----32767The range of unsigned smallint values is 0------

In a database with a large number of transactions, tables and indexes are fragmented over time. Therefore, to improve performance, you should periodically check the fragmentation of tables and indexes, and defragment them with a lot of fragmentation.

1 Application Name (application name): The name of the application. If not specified, it has a value of. NET SqlClient data Provider.2 attachdbfilename/extended Properties (extended property)/initial file name (initial file name): The name of the

Original: 01. How SQL Server reads and writes dataI. Data reading and writing process briefSQL Server, as a relational database, also maintains the acid nature of the transaction, and the database read-write conflict is controlled by the transaction

Original: In SQL Server, the view is being hackedAfter lesktop open source IM, some netizens asked how to integrate with the user system of their website after im embedding (that is, how to let embedded im directly use the original user database of

In SQL SERVER 2005/2008, two types of ranking window functions and clustered window functions are supported.For example, in SQL Server, the order number is listed in chronological order.With OrderInfo as(SELECT row_number () over (ORDER by OrderDate)

Prompt window: Steps to resolve:The first step:Enter the installation center in the SQL2008 Configuration toolStep Two:Re-enter the maintenance interface and select Version UpgradeStep Three:Enter the product key, type the keyFourth

Microsoft SQL Server provides two types of indexes: Clustered indexes (clustered index, also known as clustered indexes, clustered indexes), and nonclustered indexes (nonclustered index, also called nonclustered indexes, non-clustered indexes)Let's

1. Default conditionAfter you create a database, you typically have two files with a suffix of. mdf (primary file) and. ldf (log files) by default with only one filegroup2. Add filegroups, file groups are used to place files (users can add file

Original: The simplest way to delete all data in SQL ServerThe simplest Way to delete all data in SQL Server Author : CC Abba 2014-3-14 in fact, the method of deleting the data in the database is not complicated, why do I have to superfluous

SQL after the server changes the name Author : CC Abba 2014-6-15 in Daily SQL 2005 database operation, sometimes after the database is installed, and then renamed, causing some SQL Service is not working properly (in SQL2000 , you don't want to

　DBCC Dropcleanbuffers -- empty cache SETSTATISTICSon -- Turn on IO statistics SELECT* from person -- query statement　　　　 Pre-read: Use the estimated information to go to the hard disk to read the data to the cache. Pre-read 100

If you want to set the SQL Server database transaction isolation level to committed read-only snapshot isolationIf you run the following statement directly:ALTER Database [Mydbname] SET read_committed_snapshot onmay be blocked for a long time. My

Realize1) with the same data, return directly (return value: 0);2) The data with the same primary key, but different data, to update processing (return value: 2);3) No data, insert processing (return value: 1)."Create stored Procedure"Create proc

SQL Server paged query stored procedure used in the project."Stored Procedures"Create PROCEDURE Prcpageresult--Get the data of a page--@currPage int = 1,--The current page number (that is, top currpage)@showColumn varchar (2000) = ' * ',--the field

SQL Server shared lock, exclusive lock, update lock use previous/next 2009-11-08 00:29:17/personal Category: DatabaseView (889)/comment (0)/rating (0/0)Overview of LocksI. Why to introduce a lockConcurrent operations on a database by multiple users

Jsp adds a date to the database MS SQL SERVER: NSERT into student (studentid, time1) values ('15', getdate ()); MY SQL Insert into tablename (fieldname) values (now ()) Obtains the number of all rows of a table in the database. Connection conn =

1. What is the generation of index fragmentation? Index pages are split due to a large number of insert, modify, and delete operations in the table. If the index has high fragmentation, there are two situations: one is that it takes a lot of time to