SELECT NVL(COMM,0) AS NEW_COMM, COMM FROM EMP; NVL2函数 NVL函数有一定局限,所以就有了NVL2函数。 NVL2函数的格式如下:NVL2(expr1,expr2, expr3) NVL2函数:Oracle/PLSQL中的一个函数,NVL2(E1, E2, E3)功能: 如果E1为NULL,则函数返回E3,若E1不为null,则返回E2。 例子:如果EMP表上COMM奖金为NULL ...
一、ORACLE的NVL、NVL2、NULLIF、COALESE 1、NVL(exp1,exp2),用来判断如果字段为null就进行某些操作;如果exp1为null,返回exp2;否则返回exp1(这个函数对应MYSQL的IFNULL) selectnvl(&varA,&varB)fromdual--在oracle里'&varA'可以定义变量,可以手动输入(varA是自定义的) 2、NVL2(exp1,exp2,exp3) 如果exp1不...
如果想要修改日期的显示格式,也可以通过to_char*等函数来实现,这些后面会有单独一章讲解,其次,如果你发现你通过sqlplus无法展示的如我这样一行显示完全,可以通过设置set linesize、set pagesize、col ename for a20等等设置页面格式的命令自定义,或则通过plsql的命令行访问,博主就是用的plsql命令行展示的! 二、从表...
ExploreMicrosoft docson Coalesce function in SQL Server. You can review existingSQL Server Tutorials. Deciding between COALESCE and ISNULL in SQL Server The Many Uses of Coalesce in SQL Server SQL COALESCE, ISNULL, NULLIF in SQL Server, Oracle and PostgreSQL COALESCE SQL Function How to Use SQL...
问Oracle SQL使用CoalesceENCOALESCE (expression_1, expression_2, ...,expression_n) 依次参考各参数...
The complete guide to SQL COALESCE. Learn the syntax, parameters, use cases and find practical examples in the Hightouch SQL Dictionary.
Examples of the COALESCE Function Here are some examples of the Oracle, SQL Server, MySQL, and Postgres COALESCE function. These examples use the sample customers table that I have used for several other examples. CREATETABLEcustomers(first_name varchar2(100),last_name varchar2(100),country varc...
【Oracle】中coalesce函数的用法 1、coalesce函数的用法 1.1 取出第一个不为空的列的数据。 1.2 coalesce函数里面的数据类型,必须全部都跟第一列的数据类型一致。 原因为第一个参数为数值,第二个参数为字符串;可通过转换数据类型来使用,如下图:...
Examples of SQL COALESCE Here are a few examples to understand SQL COALESCE better. Example #1 SQL query to illustrate the use of simple COALESCE function. Code: SELECT COALESCE(NULL, NULL, NULL, 'EduCBA', NULL, NULL); Output: In this example, we can see that the COALESCE function select...
This Oracle tutorial explains how to use the Oracle/PLSQL COALESCE function with syntax and examples.Description The Oracle/PLSQL COALESCE function returns the first non-null expression in the list. If all expressions evaluate to null, then the COALESCE function will return null....