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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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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