How to run queries on live data
From Wikitech
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# Go to http://noc.wikimedia.org/dbtree/ and look for a slave database server that isn't very busy (low lag, few active threads and slow queries) and has the data you need (See https://noc.wikimedia.org/conf/highlight.php?file=db.php) | # Go to http://noc.wikimedia.org/dbtree/ and look for a slave database server that isn't very busy (low lag, few active threads and slow queries) and has the data you need (See https://noc.wikimedia.org/conf/highlight.php?file=db.php) | ||
# ssh to fenari | # ssh to fenari | ||
| − | # Connect to the slave database server with the syntax 'sql <DBNAME> -h <HOSTNAME>', for example | + | # Connect to the slave database server with the syntax 'sql <DBNAME> -h <HOSTNAME>', for example <kbd>sql enwiki -h db1001</kbd> |
# Run your query | # Run your query | ||
'''You should avoid running queries on the master databases whenever possible.''' Otherwise you will bog down performance of the live websites. If you absolutely must run a query on a master database, follow the following instructions: | '''You should avoid running queries on the master databases whenever possible.''' Otherwise you will bog down performance of the live websites. If you absolutely must run a query on a master database, follow the following instructions: | ||
# ssh to fenari | # ssh to fenari | ||
| − | # Connect to the master database server with the syntax 'sql <DBNAME>', for example | + | # Connect to the master database server with the syntax 'sql <DBNAME>', for example <kbd>sql enwiki</kbd> |
# Run your query | # Run your query | ||
[[Category:How-To]] | [[Category:How-To]] | ||
Revision as of 19:32, 23 October 2012
If you need to query the live data (rather than a dump or toolserver mirror), follow the following steps:
- Go to http://noc.wikimedia.org/dbtree/ and look for a slave database server that isn't very busy (low lag, few active threads and slow queries) and has the data you need (See https://noc.wikimedia.org/conf/highlight.php?file=db.php)
- ssh to fenari
- Connect to the slave database server with the syntax 'sql <DBNAME> -h <HOSTNAME>', for example sql enwiki -h db1001
- Run your query
You should avoid running queries on the master databases whenever possible. Otherwise you will bog down performance of the live websites. If you absolutely must run a query on a master database, follow the following instructions:
- ssh to fenari
- Connect to the master database server with the syntax 'sql <DBNAME>', for example sql enwiki
- Run your query
