For instance, we have the columnsid,name, andis_activein theColumnstable. Theis_activecolumn indicates whether a course is currently being offered. We can use a simple CASE statement to transform theis_activeva
I vaguely remember using a case clause in a select statement in a former occupation, but now that I am using mysql (with php) I am encountering my first need for it and don't know if I can do what I want. I need to add a sequencing field to my query results based upon whether ...
SQL SELECT INTO 语句 SELECT INTO 语句将数据从一个表复制到一个新表中。...SQL SELECT INTO 示例以下 SQL 语句创建 Customers 的备份副本: SELECT * INTO CustomersBackup2017 FROM Customers; 以下...SupplierName, City, Country FROM Suppliers WHERE Country='Germany'; SQL CASE 表达式 SQL CASE 表...
In a <select-case-statement> the <select-expression> is immediately evaluated and then used in the evaluation of each subsequent <case-clause> and <case-else-clause> For each <case-clause>, each contained <range-clause> is evaluated in the order defined. If a <range-clause>matchesa <sele...
TheCase Elseclause is used to indicate theelsestatementsto be executed if no match is found between thetestexpressionand anexpressionlistin any of the otherCaseselections. Although not required, it is a good idea to have aCase Elsestatement in yourSelect Caseblock to handle unforeseentestexpression...
TheCase Elseclause is used to indicate theelsestatementsto be executed if no match is found between thetestexpressionand anexpressionlistin any of the otherCaseselections. Although not required, it is a good idea to have aCase Elsestatement in yourSelect Caseblock to handle unforeseentestexpression...
This statement is used to obtain the value of boolean_expression for each WHEN statement in a specified order. Then return the first result_expression with the value TRUE
CASE statement to create or formulate a query/expression. It can be used with any statement or clause where an expression can be used, such as with a WHERE clause, with the SELECT statement, etc. This post has presented various examples to explain the usage of the case statement in ...
TheCase Elsestatement is used to introduce theelsestatementsto run if no match is found between thetestexpressionand anexpressionlistclause in any of the otherCasestatements. Although not required, it is a good idea to have aCase Elsestatement in yourSelect Caseconstruction to handle unforeseentest...
I don't understand how YOU got THAT from his simple "select x=y". His statement is (to me) a simple query that returns (yes) a boolean result, but nothing else. In any case, I solved my problem, but am curious how "select x=y" could have possibly done it....