# Data Integrity Query **URL:** \ **Category:** Percona XtraBackup\ **Created:** [March 25, 2011, 8:05am UTC](https://forums.percona.com/t/data-integrity-query/2137 "2011-03-25T08:05:54Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![bsewell](https://avatars.discourse-cdn.com/v4/letter/b/e9c0ed/32.png) [@bsewell](https://forums.percona.com/u/bsewell)\ **Post date:** [March 25, 2011, 8:05am UTC](https://forums.percona.com/t/data-integrity-query/2137/1 "2011-03-25T08:05:54Z")
Hi just doing some backup verification and noticed some small annonlymies with the data before and after backup. There are no users logged into the system as its a local VM used for testing purposes. All the other tables are an exact match. These tables do match on the table sizes but just not on the number of records in the table. I’m thinking that something must happen to these file automatically? My SQL script is as follows: select table\_name, table\_rows, engine, data\_length,data\_free from information\_schema.tables where information\_schema.tables.table\_schema = ‘alfresco’ INTO OUTFILE’/alf\_data/Backup/tmp/MySQL\_Prebackup.txt’ FIELDS TERMINATED BY ‘,’ ENCLOSED BY ‘"’ LINES TERMINATED BY ‘\n’; Just doing a sanity check and the results of the table records are as follows: Three figures all for the number of records. One before, one after percona backup but before prepare and one after prepare. There has been no restore only the backup and prepare processes have been carried out. alf\_activity\_feed 14 14 10 alf\_node 3486 3701 3650 alf\_node\_properties 2119 1495 2119 When I tried this on our live environment with users in i had the following results: alf\_child\_assoc 1331 1214 1411 alf\_node 4387 4648 4406 alf\_node\_aspects 2104 2095 2224 alf\_node\_properties 3818 4052 4271 alf\_transaction 677 571 677 jbpm\_log 2275 1865 1861 This might be because users are using the system. Just seems a bit weird that the table figures go up and down a bit.