coalesce null

Performance Comparison Between ISNULL and COALESCE in the paging mode of SQL Server, isnullcoalesce Preface In the previous section, we explained the data type and several notes in the string. In this section, we will continue to talk about the

Objective In the previous section we talked about data types and a few things to note in the string, and we went on to talk about string lines as well as other content and interspersed content, short content, in-depth explanation. (Refer to the

ObjectiveIn the previous section we talked about the data types and some of the things we need to be aware of in the string, and this section goes on to talk about string lines as well as other content and interspersed content, short content, and in-

Reprint Address: http://blog.csdn.net/dba_huangzj/article/details/8300784#Directory First look at the brief definition of Books Online Grammar Here are a few more useful examples First take a look at how this function

Turn: http://blog.csdn.net/dba_huangzj/article/details/8300784 Many people know the isnull function, but few know the coalesce function. People will accidentally use the coalesce function and find it more powerful than isnull. In fact, this function

The difference between ALTER INDEX COALESCE and ALTER INDEX rebuild:Alter index COALESCE is the leaf block that merges the same branch.and ALTER index rebuild is to re-establish a indexes, generally need twice times the size of the index space . and

IF EXISTS (SELECT * from sysobjects WHERE name = ' Prapp_invitems_insert ')DROP PROC Prapp_invitems_insertGo ------------------------------------------------------------------------------Insert a single record into Invitems--------------------------

nullif function Nullif (expression1,expression2): Given two parameters Expression1 and Expression2, if two parameters are equal, NULL is returned, otherwise the first argument is returned. Equivalent to: case when Expression1=Expression2 then NULL

SQL Server COALESCE functions detailed Many people know the IsNull function, but few people know the COALESCE function, people will inadvertently use the COALESCE function, and found that it is more powerful than isnull, in fact, so far, this

Coalesce usage: Returns the first non-empty expression in its argument. Transact-SQL Syntax conventions Grammar COALESCE (expression [,... n]) Parameters Expression An expression of any type. return type Returns the data type of the expression