The explain tells that the query is awful (it doesn't use a single key) but I'm using LIMIT 1. Is th

Posted by Ricardo on Stack Overflow See other posts from Stack Overflow or by Ricardo
Published on 2010-05-05T12:10:52Z Indexed on 2010/05/05 12:18 UTC
Read the original article Hit count: 232

Filed under:

mysql

|

query

|

explain

|

optimization

|

index

The explain command with the query:

explain SELECT * FROM leituras 
WHERE categorias_id=75 AND 
textos_id=190304 AND 
cookie='3f203349ce5ad3c67770ebc882927646' AND 
endereco_ip='127.0.0.1' 
LIMIT 1

The result:

id     select_type     table     type     possible_keys     key     key_len     ref     rows     Extra       
1      SIMPLE          leituras  ALL      (null)            (null)  (null)      (null)  1022597  Using where

Will it make any difference adding some keys on the table? Even that the query will always return only one row.

© Stack Overflow or respective owner

Related posts about mysql

How to remove MySQL completely with config and library files on ubuntu 12.04 gnome 3.0

as seen on Ask Ubuntu - Search for 'Ask Ubuntu'
I tried everything till now: sudo apt-get remove mysql-server mysql-client mysql-common sudo apt-get purge mysql-server mysql-client mysql-common sudo apt-get autoremove and even more commands... But whenever I am trying to locate mysql. I get a no. of files related to mysql command: shell>>… >>> More
mysql: Cannot load from mysql.proc. The table is probably corrupted

as seen on Server Fault - Search for 'Server Fault'
Mysql was started: /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 but when I'm trying to do something: ERROR 1548 (HY000) at line 1: Cannot… >>> More
Why is there a /etc/init.d/mysql file on this Slackware machine? How could it have gotten there?

as seen on Server Fault - Search for 'Server Fault'
A client of my IT-consulting service owns a web-development shop. He's been having problems with a Slackware 12.0 server running MySQL 5.0.67. The machine was set up by the client's sysadmin, who left on bad terms. My client no longer employs a sysadmin. As far as I can tell, the only copy of MySQL… >>> More
mysql: Bind on unix socket: Permission denied

as seen on Server Fault - Search for 'Server Fault'
Can't start mysql with: sudo /usr/bin/mysqld_safe --datadir=/srv/mysql/myDB --log-error=/srv/mysql/logs/mysqld-myDB.log --pid-file=/srv/mysql/pids/mysqld-myDB.pid --user=mysql --socket=/srv/mysql/sockets/mysql-myDB.sock --port=3700 120222 13:40:48 mysqld_safe Starting mysqld daemon with databases… >>> More
MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

as seen on SQL Authority - Search for 'SQL Authority'
MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which… >>> More

Related posts about query

sort mysql query by filtered query

as seen on Stack Overflow - Search for 'Stack Overflow'
I have two mysql queries: $sql = "SELECT * FROM content WHERE threadName LIKE '%$filter%' ORDER BY lastUpdated desc"; and $sql = "SELECT * FROM content ORDER BY lastUpdated desc"; The end result is to have all rows returned from a particular table 'content' but have those that match the variable… >>> More
How to use PHPunit's Database Test Case Methods of Query to compare with doctrine query

as seen on Stack Overflow - Search for 'Stack Overflow'
How to use PHPunit's Database Test Case Methods of Query to compare with doctrine query i m using phpunit with doctrine framework .. i want to test my doctrine query with phpunit query with using phpunit framework methods.. any buddy with Doctrine Query and PhpUnit Query plz Contact... //Bhavin… >>> More
Converting sql query to EF query - nested query in from

as seen on Stack Overflow - Search for 'Stack Overflow'
Hey guys Just wondering how the following sql query would look in linq for Entity Framework... SELECT KPI.* FROM KeyPerformanceIndicator KPI INNER JOIN ( SELECT SPP.SportProgramPlanId FROM SportProgramPlan PSPP INNER JOIN SportProgramPlan ASPP … >>> More
Sql Query - Limiting query results

as seen on Stack Overflow - Search for 'Stack Overflow'
I am quite certain we cannot use the LIMIT clause for what I want to do - so wanted to find if there are any other ways we can accomplish this. I have a table which captures which user visited which store. Every time a user visits a store, a row is inserted into this table. Some of the fields are shopping_id… >>> More
hql equivalent query to this sql query

as seen on Stack Overflow - Search for 'Stack Overflow'
Select top 1 from <tablename> what is hql query for the above ? >>> More