The NVL function in SQL replaces NULL values with a default. Learn how to use it, understand the syntax, and see how it compares to COALESCE for SQL queries.
There are several functions in SQL, such as NVL and ISNULL, that perform some kind of logic on the values that are provided. Learn what they all do and see some examples in this article. SQL Cheat Sheets: Get my SQL Cheat Sheets for Oracle, SQL Server, MySQL, and Postgres SQL Logical...
```sql SELECT last_name, salary, commission_pct, NVL2(commission_pct, ’SAL+COMM’, ’SAL’) income FROM employees; ``` 输出: DECODE() : Facilitates conditional inquiries by doing the work of a CASE or IF-THEN-ELSE statement. The DECODE function decodes an expression in a way similar...
This SQL statement would return thesupplier_namefield if thesupplier_desccontained a null value. Otherwise, it would return thesupplier_desc. Example #3: select NVL(commission, 0) from sales; This SQL statement would return 0 if thecommissionfield contained a null value. Otherwise, it would re...
如果没有任何索引，引擎将执行全表扫描。它将从堆中读取所有行，并计算 predicate 值以决定是否保留或...
在索引的范围内，在资源使用、i/o或性能方面没有区别。如果没有任何索引，引擎将执行全表扫描。它将从...
/// d ##class(PHA.TEST.SQLFunction).Nvl()ClassMethodNvl(){s myquery=3smyquery(1)="SELECT Name,"smyquery(2)="NVL(FavoriteColors,'No Preference') AS ColorChoice "smyquery(3)="FROM Sample.Person"s tStatement=##class(%SQL.Statement).%New()s qStatus=tStatement.%Prepare(.myquery)s ...
GRANT {ALL | statement[,...n]} TO security_account [ ,...n ] SQL 1001 查询全体男同学信息情况 select * from student where sex='男' 1002 查询选修了1号课的学生的学号和成绩 select sno,grade from sc where cno='1' 1003 查询1989年以前出生的学生学号和姓名和出生日期(提示请用year(...
statement.executeQuery("select it.itcod, it.itnam, it.packn, it.tradp, " + "sum(nvl(itd.slbox,0) - nvl(itd.srbox,0) - nvl(itd.brbox,0) - nvl(itd.gsbox,0)) as sbox, " +"sum(nvl(itd.slbbx,0) - nvl</e 浏览2提问于2016-10-24得票数 0 回答已采纳 ...
Look at the following SELECT statement: SELECTProductName, UnitPrice * (UnitsInStock + UnitsOnOrder) FROMProducts; In the example above, if any of the "UnitsOnOrder" values are NULL, the result will be NULL. Solutions MySQL The MySQLIFNULL()function lets you return an alternative value if...