What is the purpose of Order By 1 in SQL select statement?
I\'m reading through some old code at work, and have noticed that there are several views with an order by 1 clause. What does this accomplish?
Exampl
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it simply means sorting the view or table by 1st column of query's result.
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An example here from a sample test WAMP server database:-
mysql> select * from user_privileges; | GRANTEE | TABLE_CATALOG | PRIVILEGE_TYPE | IS_GRANTABLE | +--------------------+---------------+-------------------------+--------------+ | 'root'@'localhost' | def | SELECT | YES | | 'root'@'localhost' | def | INSERT | YES | | 'root'@'localhost' | def | UPDATE | YES | | 'root'@'localhost' | def | DELETE | YES | | 'root'@'localhost' | def | CREATE | YES | | 'root'@'localhost' | def | DROP | YES | | 'root'@'localhost' | def | RELOAD | YES | | 'root'@'localhost' | def | SHUTDOWN | YES | | 'root'@'localhost' | def | PROCESS | YES | | 'root'@'localhost' | def | FILE | YES | | 'root'@'localhost' | def | REFERENCES | YES | | 'root'@'localhost' | def | INDEX | YES | | 'root'@'localhost' | def | ALTER | YES | | 'root'@'localhost' | def | SHOW DATABASES | YES | | 'root'@'localhost' | def | SUPER | YES | | 'root'@'localhost' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'localhost' | def | LOCK TABLES | YES | | 'root'@'localhost' | def | EXECUTE | YES | | 'root'@'localhost' | def | REPLICATION SLAVE | YES | | 'root'@'localhost' | def | REPLICATION CLIENT | YES | | 'root'@'localhost' | def | CREATE VIEW | YES | | 'root'@'localhost' | def | SHOW VIEW | YES | | 'root'@'localhost' | def | CREATE ROUTINE | YES | | 'root'@'localhost' | def | ALTER ROUTINE | YES | | 'root'@'localhost' | def | CREATE USER | YES | | 'root'@'localhost' | def | EVENT | YES | | 'root'@'localhost' | def | TRIGGER | YES | | 'root'@'localhost' | def | CREATE TABLESPACE | YES | | 'root'@'127.0.0.1' | def | SELECT | YES | | 'root'@'127.0.0.1' | def | INSERT | YES | | 'root'@'127.0.0.1' | def | UPDATE | YES | | 'root'@'127.0.0.1' | def | DELETE | YES | | 'root'@'127.0.0.1' | def | CREATE | YES | | 'root'@'127.0.0.1' | def | DROP | YES | | 'root'@'127.0.0.1' | def | RELOAD | YES | | 'root'@'127.0.0.1' | def | SHUTDOWN | YES | | 'root'@'127.0.0.1' | def | PROCESS | YES | | 'root'@'127.0.0.1' | def | FILE | YES | | 'root'@'127.0.0.1' | def | REFERENCES | YES | | 'root'@'127.0.0.1' | def | INDEX | YES | | 'root'@'127.0.0.1' | def | ALTER | YES | | 'root'@'127.0.0.1' | def | SHOW DATABASES | YES | | 'root'@'127.0.0.1' | def | SUPER | YES | | 'root'@'127.0.0.1' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'127.0.0.1' | def | LOCK TABLES | YES | | 'root'@'127.0.0.1' | def | EXECUTE | YES | | 'root'@'127.0.0.1' | def | REPLICATION SLAVE | YES | | 'root'@'127.0.0.1' | def | REPLICATION CLIENT | YES | | 'root'@'127.0.0.1' | def | CREATE VIEW | YES | | 'root'@'127.0.0.1' | def | SHOW VIEW | YES | | 'root'@'127.0.0.1' | def | CREATE ROUTINE | YES | | 'root'@'127.0.0.1' | def | ALTER ROUTINE | YES | | 'root'@'127.0.0.1' | def | CREATE USER | YES | | 'root'@'127.0.0.1' | def | EVENT | YES | | 'root'@'127.0.0.1' | def | TRIGGER | YES | | 'root'@'127.0.0.1' | def | CREATE TABLESPACE | YES | | 'root'@'::1' | def | SELECT | YES | | 'root'@'::1' | def | INSERT | YES | | 'root'@'::1' | def | UPDATE | YES | | 'root'@'::1' | def | DELETE | YES | | 'root'@'::1' | def | CREATE | YES | | 'root'@'::1' | def | DROP | YES | | 'root'@'::1' | def | RELOAD | YES | | 'root'@'::1' | def | SHUTDOWN | YES | | 'root'@'::1' | def | PROCESS | YES | | 'root'@'::1' | def | FILE | YES | | 'root'@'::1' | def | REFERENCES | YES | | 'root'@'::1' | def | INDEX | YES | | 'root'@'::1' | def | ALTER | YES | | 'root'@'::1' | def | SHOW DATABASES | YES | | 'root'@'::1' | def | SUPER | YES | | 'root'@'::1' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'::1' | def | LOCK TABLES | YES | | 'root'@'::1' | def | EXECUTE | YES | | 'root'@'::1' | def | REPLICATION SLAVE | YES | | 'root'@'::1' | def | REPLICATION CLIENT | YES | | 'root'@'::1' | def | CREATE VIEW | YES | | 'root'@'::1' | def | SHOW VIEW | YES | | 'root'@'::1' | def | CREATE ROUTINE | YES | | 'root'@'::1' | def | ALTER ROUTINE | YES | | 'root'@'::1' | def | CREATE USER | YES | | 'root'@'::1' | def | EVENT | YES | | 'root'@'::1' | def | TRIGGER | YES | | 'root'@'::1' | def | CREATE TABLESPACE | YES | | ''@'localhost' | def | USAGE | NO | +--------------------+---------------+-------------------------+--------------+ 85 rows in set (0.00 sec)And when it is given additional
order by PRIVILEGE_TYPEor can be givenorder by 3. Notice the 3rd column (PRIVILEGE_TYPE) getting sorted alphabetically.mysql> select * from user_privileges order by PRIVILEGE_TYPE; +--------------------+---------------+-------------------------+--------------+ | GRANTEE | TABLE_CATALOG | PRIVILEGE_TYPE | IS_GRANTABLE | +--------------------+---------------+-------------------------+--------------+ | 'root'@'127.0.0.1' | def | ALTER | YES | | 'root'@'::1' | def | ALTER | YES | | 'root'@'localhost' | def | ALTER | YES | | 'root'@'::1' | def | ALTER ROUTINE | YES | | 'root'@'localhost' | def | ALTER ROUTINE | YES | | 'root'@'127.0.0.1' | def | ALTER ROUTINE | YES | | 'root'@'127.0.0.1' | def | CREATE | YES | | 'root'@'::1' | def | CREATE | YES | | 'root'@'localhost' | def | CREATE | YES | | 'root'@'::1' | def | CREATE ROUTINE | YES | | 'root'@'localhost' | def | CREATE ROUTINE | YES | | 'root'@'127.0.0.1' | def | CREATE ROUTINE | YES | | 'root'@'::1' | def | CREATE TABLESPACE | YES | | 'root'@'localhost' | def | CREATE TABLESPACE | YES | | 'root'@'127.0.0.1' | def | CREATE TABLESPACE | YES | | 'root'@'::1' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'localhost' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'127.0.0.1' | def | CREATE TEMPORARY TABLES | YES | | 'root'@'localhost' | def | CREATE USER | YES | | 'root'@'127.0.0.1' | def | CREATE USER | YES | | 'root'@'::1' | def | CREATE USER | YES | | 'root'@'localhost' | def | CREATE VIEW | YES | | 'root'@'127.0.0.1' | def | CREATE VIEW | YES | | 'root'@'::1' | def | CREATE VIEW | YES | | 'root'@'127.0.0.1' | def | DELETE | YES | | 'root'@'::1' | def | DELETE | YES | | 'root'@'localhost' | def | DELETE | YES | | 'root'@'::1' | def | DROP | YES | | 'root'@'localhost' | def | DROP | YES | | 'root'@'127.0.0.1' | def | DROP | YES | | 'root'@'127.0.0.1' | def | EVENT | YES | | 'root'@'::1' | def | EVENT | YES | | 'root'@'localhost' | def | EVENT | YES | | 'root'@'127.0.0.1' | def | EXECUTE | YES | | 'root'@'::1' | def | EXECUTE | YES | | 'root'@'localhost' | def | EXECUTE | YES | | 'root'@'127.0.0.1' | def | FILE | YES | | 'root'@'::1' | def | FILE | YES | | 'root'@'localhost' | def | FILE | YES | | 'root'@'localhost' | def | INDEX | YES | | 'root'@'127.0.0.1' | def | INDEX | YES | | 'root'@'::1' | def | INDEX | YES | | 'root'@'::1' | def | INSERT | YES | | 'root'@'localhost' | def | INSERT | YES | | 'root'@'127.0.0.1' | def | INSERT | YES | | 'root'@'127.0.0.1' | def | LOCK TABLES | YES | | 'root'@'::1' | def | LOCK TABLES | YES | | 'root'@'localhost' | def | LOCK TABLES | YES | | 'root'@'127.0.0.1' | def | PROCESS | YES | | 'root'@'::1' | def | PROCESS | YES | | 'root'@'localhost' | def | PROCESS | YES | | 'root'@'::1' | def | REFERENCES | YES | | 'root'@'localhost' | def | REFERENCES | YES | | 'root'@'127.0.0.1' | def | REFERENCES | YES | | 'root'@'::1' | def | RELOAD | YES | | 'root'@'localhost' | def | RELOAD | YES | | 'root'@'127.0.0.1' | def | RELOAD | YES | | 'root'@'::1' | def | REPLICATION CLIENT | YES | | 'root'@'localhost' | def | REPLICATION CLIENT | YES | | 'root'@'127.0.0.1' | def | REPLICATION CLIENT | YES | | 'root'@'::1' | def | REPLICATION SLAVE | YES | | 'root'@'localhost' | def | REPLICATION SLAVE | YES | | 'root'@'127.0.0.1' | def | REPLICATION SLAVE | YES | | 'root'@'127.0.0.1' | def | SELECT | YES | | 'root'@'::1' | def | SELECT | YES | | 'root'@'localhost' | def | SELECT | YES | | 'root'@'127.0.0.1' | def | SHOW DATABASES | YES | | 'root'@'::1' | def | SHOW DATABASES | YES | | 'root'@'localhost' | def | SHOW DATABASES | YES | | 'root'@'127.0.0.1' | def | SHOW VIEW | YES | | 'root'@'::1' | def | SHOW VIEW | YES | | 'root'@'localhost' | def | SHOW VIEW | YES | | 'root'@'localhost' | def | SHUTDOWN | YES | | 'root'@'127.0.0.1' | def | SHUTDOWN | YES | | 'root'@'::1' | def | SHUTDOWN | YES | | 'root'@'::1' | def | SUPER | YES | | 'root'@'localhost' | def | SUPER | YES | | 'root'@'127.0.0.1' | def | SUPER | YES | | 'root'@'127.0.0.1' | def | TRIGGER | YES | | 'root'@'::1' | def | TRIGGER | YES | | 'root'@'localhost' | def | TRIGGER | YES | | 'root'@'::1' | def | UPDATE | YES | | 'root'@'localhost' | def | UPDATE | YES | | 'root'@'127.0.0.1' | def | UPDATE | YES | | ''@'localhost' | def | USAGE | NO | +--------------------+---------------+-------------------------+--------------+ 85 rows in set (0.00 sec)DEFINITIVELY, a long answer and alot of scrolling. Also I struggled hard to pass the output of the queries to a text file. Here is how to do that without using the annoying
into outfilething-tee E:/sqllogfile.txt;
And when you are done, stop the logging-
tee off;
Hope it adds more clarity.
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As mentioned in other answers
ORDER BY 1orders by the first column.I came across another example of where you might use it though. We have certain queries which need to be ordered select the same column. You would get a SQL error if ordering by
Namein the below.SELECT Name, Name FROM Segment ORDER BY 1讨论(0) -
This is useful when you use set based operators e.g. union
select cola from tablea union select colb from tableb order by 1;讨论(0) -
I believe in Oracle it means order by column #1
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Also see:
http://www.techonthenet.com/sql/order_by.php
For a description of order by. I learned something! :)
I've also used this in the past when I wanted to add an indeterminate number of filters to a sql statement. Sloppy I know, but it worked. :P
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