In case you wish to delete duplicate rows and keep the lowest custid, then you can use the same query but with slight variation in the condition as shown in the following statement: Delete from customers where custid IN (Select c1.custid FROM customers as c1 INNER JOIN customers as c2 ON...
Thus, if you have transactions that update, insert, or delete many rows, making the log buffer larger saves disk I/O. For related information, see Memory Configuration, and Section 10.5.4, “Optimizing InnoDB Redo Logging”. For general I/O tuning advice, see Section 10.5.8, “Optimizing ...
void set_sent_row_count (ha_rows count) void inc_sent_row_count (ha_rows count) void inc_examined_row_count (ha_rows count) void inc_status_created_tmp_disk_tables () void inc_status_created_tmp_tables () void inc_status_count_hit_tmp...
The so-called phantom problem occurs within a transaction when the same query produces different sets of rows at different times. For example, if a SELECT is executed twice, but returns a row the second time that was not returned the first time, the row is a“phantom”row. 所谓的幻读(ph...
The following bug:https://bugs.mysql.com/bug.php?id=98995is a duplicate of this one. [23 Mar 2020 11:12] MySQL Verification Team Disabling the AHI is not a solution in all cases. If the purge thread wakes up or the master thread checks if tables need eviction from cache, this will...
Bug #114065marked as duplicate of this one. [10 Mar 2024 21:32] Ryousuke Tanida Hello. As reported inBug #114065, it seems that a similar issue has occurred. Currently, a timeout occurs when pausing due to debugging, so proper development is not possible with the current version. When ...
If you want to add another slave to the existing replication configuration then you can do so without stopping the master. Instead, you duplicate the settings on the slaves by making a copy of one of the slaves. To duplicate the slave: ...
support one snapshot per volume, and you need to remove it to be able to take your next backup. B. The snapshot size continue to grow as changes to the volume are made. C. The snapshots takea significant amount of disk space as they are a duplicate copy of the data. D. ...
Keeping history records usually requires you to duplicate rows. With standard MySQL syntax you can create a query like this: INSERT INTO tablename SELECT * FROM tablename WHERE somefield = 'somevalue' The problem is that this won't work if you are using an auto_numbering key id field. Th...
You can ignore all of the query error messages (for exampleUnknown column,Duplicate column name, etc). Log into the server using the permissions from youroldMySQL installation: C:\Program Files\mysql50\bin>mysql -u root -p mysql The upgrade script gives some privilges that you probably don...