Re: unexpected result for wastedbytes query after vacuum full

2019-12-10 Thread Guillaume Lelarge
Le ven. 6 déc. 2019 à 18:18, Mike Schanne a écrit : > Hi all, > > > > This question is somewhat related to my previous question: > > > https://www.postgresql.org/message-id/0871fcf35ceb4caa8a2204ca9c38e330%40USEPRDEX1.corp.kns.com > > > > I was attempting to measure the benefit of doing a VACUUM

Re: Specific query taking time to process

2019-12-10 Thread Justin Pryzby
On Mon, Dec 09, 2019 at 10:39:38PM +, Fahiz Mohamed wrote: > Thank you very much for your prompt responses. > > I have analysed more regarding this and found the long running query. > > I ran "explain analyse" on this query and I got following result. (We have 2 > identical DB instances and

Re: unexpected result for wastedbytes query after vacuum full

2019-12-10 Thread Jeff Janes
On Tue, Dec 10, 2019 at 11:43 AM Guillaume Lelarge wrote: This query uses the column statistics to estimate bloat. AFAIK, json > columns don't have statistics, so the estimation can't be relied on (for > this specific table at least). > This was true prior to 9.5 (for xml at least, I don't know

Re: Specific query taking time to process

2019-12-10 Thread Michael Lewis
On Mon, Dec 9, 2019 at 3:39 PM Fahiz Mohamed wrote: > I ran "explain analyse" on this query and I got following result. (We have > 2 identical DB instances and they consist of same data. Instane 1 took 20+ > second to process and instance 2 took less than a second) > > Instance 1: (This is used

Re: Specific query taking time to process

2019-12-10 Thread Fahiz Mohamed
Thank you very much for your prompt responses. I have analysed more regarding this and found the long running query. I ran "explain analyse" on this query and I got following result. (We have 2 identical DB instances and they consist of same data. Instane 1 took 20+ second to process and