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I'm trying to figure out how to optimize a very slow query in MySQL (I didn't design this): SELECT COUNT(*) FROM change_event me WHERE change_event_id > '1212281603783391'; +----------+ | COUNT(*) | +----------+ | 3224022 | +----------+ 1 row in set (1 min 0.16 sec) Comparing that to a full count: select count(*) from change_event; +----------+ | count(*) | +----------+ | 6069102 | +----------+ 1 row in set (4.21 sec) The explain statement doesn't help me here: explain SELECT COUNT(*) FROM change_event me WHERE change_event_id > '1212281603783391'\G *************************** 1. row *************************** id: 1 select_type: SIMPLE table: me type: range possible_keys: PRIMARY key: PRIMARY key_len: 8 ref: NULL rows: 4120213 Extra: Using where; Using index 1 row in set (0.00 sec) OK, it still thinks it needs roughly 4 million entries to count, but I could count lines in a file faster than that! I don't understand why MySQL is taking this long. Here's the table definition: CREATE TABLE `change_event` ( `change_event_id` bigint(20) NOT NULL default '0', `timestamp` datetime NOT NULL, `change_type` enum('create','update','delete','noop') default NULL, `changed_object_type` enum('Brand','Broadcast','Episode','OnDemand') NOT NULL, `changed_object_id` varchar(255) default NULL, `changed_object_modified` datetime NOT NULL default '1000-01-01 00:00:00', `modified` datetime NOT NULL default '1000-01-01 00:00:00', `created` datetime NOT NULL default '1000-01-01 00:00:00', `pid` char(15) default NULL, `episode_pid` char(15) default NULL, `import_id` int(11) NOT NULL, `status` enum('success','failure') NOT NULL, `xml_diff` text, `node_digest` char(32) default NULL, PRIMARY KEY (`change_event_id`), KEY `idx_change_events_changed_object

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