其中,condition是要检查的条件,value_if_true是当条件为真时要返回的值,value_if_false是当条件为假时要返回的值。例如,如果要根据一个列的值是否为NULL来返回不同的结果,可以使用以下代码: IF(column_name IS NULL, 'NULL', 'NOT NULL') BigQuery的优势包括: 弹性扩展:BigQuery可以处理大规模的数据集,并且...
COALESCE … statement to return 0 as the alternative value when bonus value is NULL: SELECT emp_no, salary, from_date, to_date, COALESCE(bonus, 0) FROM salaries; In MySQL you can also use IFNULL function to return 0 as the alternative for the NULL values: SELECT emp_no, salary, ...
SQL> DECLARE 2 testvalue INT; 3 BEGIN 4 testvalue := 100; 5 6 IF testvalue > 100 THEN 7 dbms_output.put_line( '100+' ); 8 ELSIF testvalue = 100 THEN 9 dbms_output.put_line( '100' ); 10 ELSE 11 dbms_output.put_line( '100-' ); 12 END IF; 13 14 END; 15 /100PL/SQ...
SQL 条件语句 (IF, CASE WHEN, IFNULL) 1、IF 1.1 表达式: IF( expr1 , expr2 , expr3 ) expr1条件,条件为true,则值是expr2 ,false,值就是expr3 示例; SELECT o.id,u.account,catagory
when 列名=条件值2 then 选项2……. else 默认值 end 例如: updateemployeesete_wage=casewhenjob_level='1'thene_wage*1whenjob_level='2'thene_wage*2whenjob_level='3'thene_wage*3elsee_wage*4end IFNULL函数用法 MySQL IFNULL函数是MySQL控制流函数之一,它接受两个参数,如果不是NULL,则返回第一个...
IFEXISTS(SELECT*FROMcategory_infoWHEREcategory_name='Electronics')BEGINselect*fromcategory_info;ENDELSEBEGINinsertintocategory_info(category_name)values('Electronics');END Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax...
columnLabelthe label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column Returns: the column value; if the value is SQLNULL, the value returned is null ...
在SQL SELECT中执行IF ... THEN,可以使用CASE语句。CASE语句允许您根据特定条件返回不同的值。以下是一个示例: 代码语言:sql 复制 SELECTcolumn1,column2,CASEWHENcondition1THENvalue1WHENcondition2THENvalue2ELSEvalue3ENDASresult_columnFROMtable_nameWHEREsome_condition; ...
If no records are returned are rs.BOF and rs.EOF both set? (If rs.BOF And rs.EOF Then) If Null then 0 else Value IIF Like and Not Like Or Or Or IIF Statement for Report Textbox Value IIf Statement with an wildcard IIF(IsNull) formula trouble ...
value of a is : 10 PL/SQL procedure successfully completed. 示例- 2 我们在PL/SQL变量类型中创建了一个表和几个记录,参考以下语句操作上述表和数据 - DECLAREc_id customers.id%type :=1; c_sal customers.salary%type;BEGINSELECTsalaryINTOc_salFROMcustomersWHEREid=c_id; ...