Use defined variable in new select clause : Select « Select Clause « SQL / MySQL

SQL / MySQL
1. Backup Load
2. Command MySQL
3. Cursor
4. Data Type
5. Database
6. Date Time
7. Flow Control
8. Function
9. Insert Delete Update
10. Join
11. Key
12. Math
13. Procedure Function
14. Select Clause
15. String
16. Table Index
17. Transaction
18. Trigger
19. User Permission
20. View
21. Where Clause
Microsoft Office Word 2007 Tutorial
Java
Java Tutorial
Java Source Code / Java Documentation
Java Open Source
Jar File Download
Java Articles
Java Products
Java by API
C# / C Sharp
C# / CSharp Tutorial
ASP.Net
JavaScript DHTML
JavaScript Tutorial
JavaScript Reference
HTML / CSS
HTML CSS Reference
C / ANSI-C
C Tutorial
C++
C++ Tutorial
PHP
Python
SQL Server / T-SQL
Oracle PL / SQL
Oracle PL/SQL Tutorial
PostgreSQL
MySQL Tutorial
VB.Net
VB.Net Tutorial
SQL / MySQL » Select Clause » Select 
Use defined variable in new select clause

/*
mysql> SELECT * FROM report;
+---------+--------+-------+
| article | dealer | price |
+---------+--------+-------+
|    0001 | A      |  4.45 |
|    0001 | B      |  5.45 |
|    0002 | A      | 16.67 |
|    0003 | B      |  6.12 |
|    0003 | C      |  2.78 |
|    0003 | D      |  2.34 |
|    0004 | D      | 21.29 |
+---------+--------+-------+
7 rows in set (0.00 sec)

mysql> SELECT @min_price:=MIN(price),@max_price:=MAX(price) FROM report;
+------------------------+------------------------+
| @min_price:=MIN(price) | @max_price:=MAX(price) |
+------------------------+------------------------+
|                   2.34 |                  21.29 |
+------------------------+------------------------+
1 row in set (0.00 sec)

mysql> /* Using User Variables */
mysql> SELECT FROM report WHERE price=@min_price OR price=@max_price;
+---------+--------+-------+
| article | dealer | price |
+---------+--------+-------+
|    0003 | D      |  2.34 |
|    0004 | D      | 21.29 |
+---------+--------+-------+
rows in set (0.00 sec)


*/
Drop table report;  


CREATE TABLE report (
       article INT(4UNSIGNED ZEROFILL DEFAULT '0000' NOT NULL,
       dealer  CHAR(20)                 DEFAULT ''     NOT NULL,
       price   DOUBLE(16,2)             DEFAULT '0.00' NOT NULL,
       PRIMARY KEY(article, dealer));


INSERT INTO report VALUES (1,'A',4.45),
                        (1,'B',5.45),
                        (2,'A',16.67),
                        (3,'B',6.12),
                        (3,'C',2.78),
                        (3,'D',2.34),
                        (4,'D',21.29);
    
SELECT FROM report;    

SELECT @min_price:=MIN(price),@max_price:=MAX(priceFROM report;
  
/* Using User Variables */
SELECT FROM report WHERE price=@min_price OR price=@max_price;


           
       
Related examples in the same category
1. Define and use variable in select clause
2. Select clause with condition
3. Choose specific columns
4. Reference column in select command
5. Performing Mathematics
6. Simple Retrieval:Returning Multiple Columns
7. Simple Retrieval:Returning a Single Column
8. Simple Retrieval: Returning All Columns
9. Performing a Single Row INSERT
10. Retrieve all columns in a table
w__w__w_._j_a___va_2__s_.___c_om | Contact Us
Copyright 2003 - 08 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.