IF Boolean_expression { sql_statement | statement_block } [ ELSE { sql_statement | statement_block } ]Boolean_expression: A boolean expression that returns TRUE or FALSE. If the Boolean expression contains a SELECT statement then it should be enclosed in parentheses. ...
You can nest IF statements so that alternative IF statements are invoked, depending on whether the conditions of an outer IF statement evaluate to TRUE or FALSE. In the following example, the outer IF...THEN...ELSE statement tests whether or not an employee has a commission. The inner IF....
SQL语句大全中的sql语句备忘录—sql日常使用指北 9、说明:创建视图:create view viewname as select statement 删除视图:drop view viewname10、说明:几个简单的基本的sql语句选择:select...RecID 是自增长字段, 写一个SQL语句, 找出表的第31到第40个记录。 ...Transact-SQL 语句影响的行数的信息。...SET ...
The condition in SQL IF Statement should return a Boolean value to evaluate SQL IF语句中的条件应返回一个布尔值以求值 We can specify a Select statement as well in a Boolean expression, but it should enclose in parentheses 我们也可以在布尔表达式中指定Select语句,但应将其括在括号中 We can use ...
如果XML元素嵌入在<script>XML元素中,则可以在注释值中为动态SQL使用XML元素: @Select("<script>SELECT ...</script>") 但是使用<include>元素会触发SQL Mapper配置解析异常,由以下原因引起: org.apache.ibatis.builder.BuilderException: Unknown element in SQL statement. at org.apache.ibatis.scripting.xmltags....
如果XML元素嵌入在<script>XML元素中,则可以在注释值中为动态SQL使用XML元素: @Select("<script>SELECT ...</script>") 但是使用<include>元素会触发SQL Mapper配置解析异常,由以下原因引起: org.apache.ibatis.builder.BuilderException: Unknown element in SQL statement. at org.apache.ibatis.scripting.xmltags....
SQL Statement is: SELECT FROM subscribers WHERE (username='".$user1."' AND userpass='".$pass1."') Then I would like to have an IF statement that interrogates something that would be 0 or null if there were no records found on the select. ...
The following example uses an if statement to check if a query returns any rows: do $$ declare selected_film film%rowtype; input_film_id film.film_id%type = 0; begin select * from film into selected_film where film_id = input_film_id; if not found then raise notice'The film % co...
如果XML元素嵌入在<script>XML元素中,则可以在注释值中为动态SQL使用XML元素: @Select("<script>SELECT ...</script>") 但是使用<include>元素会触发SQL Mapper配置解析异常,由以下原因引起: org.apache.ibatis.builder.BuilderException: Unknown element in SQL statement. at org.apache.ibatis.scripting.xmltags....
如果XML元素嵌入在<script>XML元素中,则可以在注释值中为动态SQL使用XML元素: @Select("<script>SELECT ...</script>") 1. 但是使用<include>元素会触发SQL Mapper配置解析异常,由以下原因引起: org.apache.ibatis.builder.BuilderException: Unknown element in SQL statement. at ...