2015-12-12 21:04:15 mw1140 enwiki exception ERROR: [7984dda5] /w/api.php?pageids=5137507&action=query&rvstartid=654799748&rvprop=timestamp%7Csha1%7Cuser%7Cids&rvlimit=3&prop=revisions&format=json&rvend=2015-04-05T16%3A58%3A16Z&rvdir=newer   DBQueryError from line 1090 of /srv/mediawiki/php-1.27.0-wmf.8/includes/db/Database.php: A connection error occured. 
Query: SELECT  rev_id,rev_page,rev_text_id,rev_timestamp,rev_comment,rev_user_text,rev_user,rev_minor_edit,rev_deleted,rev_len,rev_parent_id,rev_sha1,rev_content_format,rev_content_model,page_namespace,page_title,page_id,page_latest,page_is_redirect,page_len,user_name  FROM `revision` INNER JOIN `page` ON ((page_id = rev_page)) LEFT JOIN `user` ON ((rev_user != 0) AND (user_id = rev_user))  WHERE (rev_timestamp<='20150405165816') AND (rev_id>='654799748') AND rev_page = '5137507'  ORDER BY rev_timestamp,rev_id LIMIT 4  
Function: ApiQueryRevisions::run
Error: 2013 Lost connection to MySQL server during query (10.64.48.20)
 {"exception_id":"7984dda5"} 
[Exception DBQueryError] (/srv/mediawiki/php-1.27.0-wmf.8/includes/db/Database.php:1090) A connection error occured. 
Query: SELECT  rev_id,rev_page,rev_text_id,rev_timestamp,rev_comment,rev_user_text,rev_user,rev_minor_edit,rev_deleted,rev_len,rev_parent_id,rev_sha1,rev_content_format,rev_content_model,page_namespace,page_title,page_id,page_latest,page_is_redirect,page_len,user_name  FROM `revision` INNER JOIN `page` ON ((page_id = rev_page)) LEFT JOIN `user` ON ((rev_user != 0) AND (user_id = rev_user))  WHERE (rev_timestamp<='20150405165816') AND (rev_id>='654799748') AND rev_page = '5137507'  ORDER BY rev_timestamp,rev_id LIMIT 4  
Function: ApiQueryRevisions::run
Error: 2013 Lost connection to MySQL server during query (10.64.48.20)

  #0 /srv/mediawiki/php-1.27.0-wmf.8/includes/db/Database.php(1030): DatabaseBase->reportQueryError(string, integer, string, string, boolean)
  #1 /srv/mediawiki/php-1.27.0-wmf.8/includes/db/Database.php(1572): DatabaseBase->query(string, string)
  #2 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiQueryBase.php(376): DatabaseBase->select(array, array, array, string, array, array)
  #3 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiQueryRevisions.php(317): ApiQueryBase->select(string)
  #4 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiQueryRevisionsBase.php(43): ApiQueryRevisions->run()
  #5 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiQuery.php(287): ApiQueryRevisionsBase->execute()
  #6 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiMain.php(1306): ApiQuery->execute()
  #7 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiMain.php(460): ApiMain->executeAction()
  #8 /srv/mediawiki/php-1.27.0-wmf.8/includes/api/ApiMain.php(432): ApiMain->executeActionWithErrorHandling()
  #9 /srv/mediawiki/php-1.27.0-wmf.8/api.php(83): ApiMain->execute()
  #10 /srv/mediawiki/w/api.php(3): include(string)
  #11 {main}

> explain SELECT  rev_id,rev_page,rev_text_id,rev_timestamp,rev_comment,rev_user_text,rev_user,rev_minor_edit,rev_deleted,rev_len,rev_parent_id,rev_sha1,rev_content_format,rev_content_model,page_namespace,page_title,page_id,page_latest,page_is_redirect,page_len,user_name  FROM `revision` INNER JOIN `page` ON ((page_id = rev_page)) LEFT JOIN `user` ON ((rev_user != 0) AND (user_id = rev_user))  WHERE (rev_timestamp<='20150405165816') AND (rev_id>='654799748') AND rev_page = '5137507'  ORDER BY rev_timestamp,rev_id LIMIT 4
    -> ;
+------+-------------+----------+--------+----------------------------------------------------------------+---------------+---------+--------------------------+-----------+-------------+
| id   | select_type | table    | type   | possible_keys                                                  | key           | key_len | ref                      | rows      | Extra       |
+------+-------------+----------+--------+----------------------------------------------------------------+---------------+---------+--------------------------+-----------+-------------+
|    1 | SIMPLE      | page     | const  | PRIMARY                                                        | PRIMARY       | 4       | const                    |         1 |             |
|    1 | SIMPLE      | revision | range  | PRIMARY,rev_id,rev_timestamp,page_timestamp,rev_timestamp_user | rev_timestamp | 20      | NULL                     | 571304301 | Using where |
|    1 | SIMPLE      | user     | eq_ref | PRIMARY                                                        | PRIMARY       | 4       | enwiki.revision.rev_user |         1 | Using where |
+------+-------------+----------+--------+----------------------------------------------------------------+---------------+---------+--------------------------+-----------+-------------+
3 rows in set (0.47 sec)

explain SELECT  rev_id,rev_page,rev_text_id,rev_timestamp,rev_comment,rev_user_text,rev_user,rev_minor_edit,rev_deleted,rev_len,rev_parent_id,rev_sha1,rev_content_format,rev_content_model,page_namespace,page_title,page_id,page_latest,page_is_redirect,page_len,user_name  FROM `revision` INNER JOIN `page` ON ((page_id = rev_page)) LEFT JOIN `user` ON ((rev_user != 0) AND (user_id = rev_user))  WHERE (rev_id>=65479974) AND rev_page = '5137507'  ORDER BY rev_timestamp,rev_id LIMIT 4;
+------+-------------+----------+--------+-------------------------------+---------------+---------+--------------------------+------+-------------+
| id   | select_type | table    | type   | possible_keys                 | key           | key_len | ref                      | rows | Extra       |
+------+-------------+----------+--------+-------------------------------+---------------+---------+--------------------------+------+-------------+
|    1 | SIMPLE      | page     | const  | PRIMARY                       | PRIMARY       | 4       | const                    |    1 |             |
|    1 | SIMPLE      | revision | index  | PRIMARY,rev_id,page_timestamp | rev_timestamp | 16      | NULL                     | 2564 | Using where |
|    1 | SIMPLE      | user     | eq_ref | PRIMARY                       | PRIMARY       | 4       | enwiki.revision.rev_user |    1 | Using where |
+------+-------------+----------+--------+-------------------------------+---------------+---------+--------------------------+------+-------------+
3 rows in set (0.05 sec)