var_paramsql = sqlClient.HiSql(@"select * from Hi_FieldModel where tabname in (@TabName) and fieldname=@fieldname and tabname in (select tabname from hi_tabmodel where tabname in (@TabName) )",new{ TabName =newList<string> {"Hi_TestQuery","Hi_FieldModel"}, FieldName ="DbServ...
The key takeaway is that you should be careful with “else 0” when using CASE WHEN. It doesn’t have any effect with SUM, but it has a huge effect on AVG. 4. JOINs ON columns with missing values There are 4 different JOINs in SQL: Inner, Outer, Left and Right. When we use JOI...
In order to have a table to demonstrate using the CASE expression I will be using the script in Listing 1 to create a sample table namedMyOrder. If you would like to follow along with my examples and run them on your SQL Server instance you can create this table in a database of you...
We have constantly issues with different kinds of customers and based on their status or payment history, you want to join them to the loyalty tables. The focus was to come up with a solution that minimises the extra reads on the other tables but also to add this to a stored proc to m...
问where子句中的SQL using caseENWhere 是一个约束声明，使用Where约束来自数据库的数据，Where是在结果...
9. CASE WHEN 的用法 Use CASE to show thenameof each teacher followed by 'Sci' if the teacher is indept1 or 2 and 'Art' otherwise. SELECT name, (CASE WHEN dept IN (1, 2) THEN 'Sci' ELSE 'Art' END) FROM teacher 10. Use CASE to show the name of each teacher followed by 'Sci...
Using CASE 9.Use CASE to show the name of each teacher followed by 'Sci' if the teacher is in dept 1 or 2 and 'Art' otherwise. 请使用CASE显示每个教师的姓名,如果教师在部门1或2中,显示“Sci”,否则显示“Art”。 select name,case when dept in (1,2) then 'Sci' else 'Art' end from...
To script the view in SQL Server Management Studio, in Object Explorer, locate the view under the Views folder for the AdventureWorks2022 database. Right-click the view name, and then select Script View as. Related content FROM clause (Transact-SQL) CASE (Transact-SQL)...
CASE must include the following components: WHEN, THEN, and END. ELSE is an optional component. You can make any conditional statement using any conditional operator (like WHERE ) between WHEN and THEN. This includes stringing together multiple conditional statements using AND and OR. You can inc...
“month bucket”, then the sales amount is added using SUM; if not, then NULL is specified, thereby avoiding adding anything to the SUM. Using CASE expressions in this manner simplifies aggregation and reporting. It provides a quick way of transforming normalized data structures into the more ...