MySQL is the main database for, and back in the day, when a number of PlanetScale folks worked there, we had to do this kind of counting differently. It is clashing with other competing transactions. In fact, until a recent version, you were guaranteed to get it sorted by the GROUP BY. Without the ORDER BY (ASC or DESC), you will probably get the output sorted by col. If the link to a subquery fails, the count is NULL, the function IFNULL replaces that with 0. COUNT() can only be used with HAVING and must be used after GROUP BY statement Please find the following example: SELECT COUNT(), MDirector.PID FROM Movie INNER JOIN MDirector ON Movie.MID MDirector.MID GROUP BY MDirector. The left join makes sure the every video is selected, and that's why IFNULL(.) is added. I added this reference to the videotitle which makes sure the count is done for every videotitle. COUNT() counts the number of rows, so the query to count your animals looks. SELECT col, COUNT() FROM tbl GROUP BY col - no ORDER BY There definitely is an extra sort. There is no reference to a videotitle in this count. Counting the total number of animals you have is the same question as How. You can see that this transaction has been waiting a significant amount of time to acquire a lock to increment the counter on this single row. MySQL ORDER BY multiple column ASC and DESC Ask Question Asked 10 years, 7 months ago Modified 6 months ago Viewed 138k times 34 I have 2 MYSQL tables, users and scores. SELECT col, COUNT() FROM tbl GROUP BY col ORDER BY COUNT() DESC versus. Record lock, heap no 2 PHYSICAL RECORD: n_fields 7 compact format info bits 0 mysql> SELECT pubid,GROUPCONCAT (DISTINCT cateid) -> FROM bookmast -> GROUP BY pubid -> ORDER BY GROUPCONCAT (DISTINCT cateid) ASC +-+-+ pubid GROUPCONCAT (DISTINCT cateid) +-+-+ P003 CA001,CA003 P005 CA001,CA004 P001 CA002,CA004 P0. RECORD LOCKS space id 2 page no 4 n bits 184 index PRIMARY of table `github`.`downloads` trx id 79853106 lock_mode X locks rec but not gap waiting TRX HAS BEEN WAITING 5 SEC FOR THIS LOCK TO BE GRANTED: Sang at 16:14 Add a comment 4 Answers Sorted by: 77 SELECT count (City), City FROM table GROUP BY City ORDER BY count (City) OR SELECT count (City) as count, City FROM table GROUP BY City ORDER BY count Ahh, sorry, I was misinterpreting your question. UPDATE slotted_counters SET count = count + 1 WHERE id = 1 1,888 6 24 34 Exact Answer /questions/26187033/ A. MySQL thread id 24, OS thread handle 6281670656, query id 107 localhost root updating LOCK WAIT 2 lock struct(s), heap size 1128, 1 row lock(s) But this syntax was removed in MySQL 8.0 and alternative is GROUP BY col1 ORDER BY col1 ASC/DESC. TRANSACTION 79853106, ACTIVE 5 sec starting index read
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