In a DECODE function, Oracle considers two nulls to be equivalent. If expr is null, then Oracle returns the result of the first search that is also null. 但是要注意的是,为这条SQL选择索引,只能对id列创建,不能对decode函数创建,因为Oracle不能基于未知的用户输入创建索...
sqllite decode函数 SQLite does not have a built-in DECODE function like some other database systems. However, you can achieve similar functionality using the CASE statement. The CASE statement allows you to define multiple conditions and return differentvalues based on those conditions. Here is an...
You could use the decode function in an SQL statement as follows: select supplier_name,decode(supplier_id,1000,'IBM',10001,'Microsoft','1002','Hewlett Packard','Gateway') result from suppliers; 上面的sql语句相当于下面的IF-THEN-ELSE : IF supplier_id = 10000 THEN result := 'IBM'; ELSIF ...
In Oracle/PLSQL, thedecodefunction has the functionality of an IF-THEN-ELSE statement. The syntax for thedecodefunction is: decode( expression , search , result [, search , result]… [, default] ) expressionis the value to compare. searchis the value that is compared againstexpression. res...
You could use the decode function in an SQL statement as follows:select supplier_name,decode(supplier_id,1000,'IBM',10001,'Microsoft','1002','Hewlett Packard','Gateway') result from suppliers;上面的sql语句相当于下面的IF-THEN-ELSE :IF supplier_id = 10000 THENresult := 'IBM';ELSIF supplier...
In Oracle/PLSQL, the decode function has the functionality of an IF-THEN-ELSE statement. The syntax for the decode function is: decode( expression , search , result [, search , result]... [, defaul ...
The DECODE function in Oracle is a versatile and powerful tool that allows users to perform conditional transformations on data within an SQL query. It is similar to the CASE statement, but it offers a more compact syntax, making it a popular choice for simplifying complex queries and improving...
We use the DECODE function in the order table to clearly convert the order processing status indicator, which is like showing the way to a lost person. 4.他发现DECODE函数在处理性别代码时超级方便,就像一键把黑白照片变成彩色照片那么简单。He found that the DECODE function is extremely convenient ...
You could use the decode function in an SQL statement as follows: select supplier_name,decode(supplier_id,1000,'IBM',10001,'Microsoft','1002','Hewlett Packard','Gateway') result from suppliers; 上面的sql语句相当于下面的IF-THEN-ELSE : ...
...2 他的精髓就在于,decode函数中,Oracle会认为两个空值是等价的,官方文档的介绍如下,这就解决了(null=null)问题, In a DECODE function, Oracle considers...但是要注意的是,为这条SQL选择索引,只能对id列创建,不能对decode函数创建,因为Oracle不能基于未知的用户输入创建索引数据, SQL> select * ...