Question : In our games we have a quartely league system. Every 3 months, the current season ends and all […]
Category: Query Performance
What is the performance impact of indexing a frequently updated column?
Question : I just want to know if I’m doing this right. I’ve searched google for hours already and I […]
Inhibiting results to pane in SSMS (TSQL language) via script
Question : I found that one could use a menu to “discard” results in SSMS (TSQL language). Please see: Original […]
too many entries for one single session and serila# in V$Session_longops
Question : I have a concern with the entries in v$session_longops. I used a query to identify query running from […]
How to performantly query using a function applied to an MySQL auto-increment column?
Question : I have a users table in MySQL 8 with an auto-increment id as primary key: CREATE TABLE users […]
PostgreSQL chooses to seq scan huge table instead of index lookup
Question : I have a table, account_balance, with primary key (address, timestamp, currency). This table is pretty big, having nearly […]
How to improve this query so it’ll run quicker
Question : I’ve got this query: SELECT m.vlanID, v.vlan_name, m.interfaceName, count(m.macAddress) as mac, n.nd_name, p.interfaceDescription, p.interfacePortType FROM macs m, network_devices […]
Improving join query performance with limit and index
Question : I have a query across two large tables. The first records the latest user activity at a location, […]
Is pg12 cache used with two SELECT on same table but different fields
Question : Figure a table with fields a, b and c Figure two requests on this table : SELECT a, […]
INSERT INTO with SELECT subquery db2 9.5
Question : I have the following query that takes 4 seconds to execute: SELECT TX.* FROM TABLE_X TX INNER JOIN […]