许多人在写SQL时都想用if，下面教你正确使用方法。 1、 先准备好待处理的数据，见下图所示。 2、 许多人使用时习惯在select语句中直接嵌入if条件，所示。 3、 在SELECT语句中，通常使用CASE来实现IF的功能，具体用法所示。 4、 随后即可得出if语句的执行结果 ...

One of the most common problems when running SQL Servers is slow queries. The help desk or database team usually hears that described as the application is slow or ...

Well, if you happen to be using Sql Server you can do that sort of thing in T-Sql. In Oracle, you can also accomplish the same thing using pl/sql. Either way i'd do it in a stored ...

Specifies the current catalog name. To change it, type a two-level name or ? to list all possible catalogs. Then make a selection from the resulting Select a Member window. Displays the number of ...

Read this SQL tutorial to learn when to use SELECT, JOIN, subselects and UNION to access multiple tables with a single statement. It’s sometimes difficult to know which SQL syntax to use when ...

A message appears at the top of the SQL Editor window to indicate which SQL is being used. If you need to use a different set of tables, you can create a new Query Manager or talk to your SAS Support ...