sql server null functions

1 Introduction to null valuesNULL is a unique data type in the database. If a column in a record is NULL, the value of this column is unknown and uncertain. Since it is unknown, there are several possibilities. Therefore, NULL is not a definite

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

13. T-SQL and SQL query AnalyzerWhat is SQL?What is T-SQL?Introduce new features of T-SQLHow to Use T-SQLSummaryIn this chapter, we will introduce some basic concepts about the Structured Query Language and transact-SQL and their differences. This

In the Access Project (that is, the. ADP file) linked to an SQL Server database, the access function that you frequently use is usually not supported. But most of the time, you can use a Transact-SQL (T-SQL) function supported by SQL Server. One

SQL has many built-in functions that can be used for counting and computation.Syntax of the functionThe syntax for the built-in SQL function is:SELECT function (column) from tableTypes of functionsIn SQL, there are several kinds of basic function

MS SQL Server Query optimization methodThere are many reasons for the slow speed of queries, which are common1, no indexes, or no indexes (this is the most common problem with query slowness, is the flaw in programming)2, I/o throughput is small,

18. Create and use a view tableView tableView table conceptsCreate a viewModify and delete a tableEnhanced viewing table functionality in SQL Server 2000SummaryIn Chapter 17th, we learned about indexes. indexes are a secondary database structure

1.NULL meaning is the missing value (missing value).2. Three value logic (Three-valued-logic:true,false,unknown). There are three logical predicates in SQL: Ture,false,unknown. In most programming language only True and false in SQL , and all of the

I found that Update DBO. tblinvtransactionSet area_type = 'groups ',Where (area_type = NULL)The result is zero. Then find the following articleChange Update DBO. tblinvtransactionSet area_type = 'group'Where (area_type is null)OK. A problem

access|server|sql| Comparison | tips Background database:[Microsoft Access]And[Microsoft SQL Server]After the replacement, the ASP code should note some of the areas to be modified: [One] connection problem (for example)[Microsoft Access]Constr =