For questions about making database queries run faster.
I have one very dirty query that per sure can be optimized because there are so many CASE statements in …
sql sql-server tsql query-optimization case-statementI've seen a few examples of passing an :include hash value when calling one of ActiveRecord's find methods in Rails. …
ruby-on-rails query-optimization entity-relationship select-n-plus-1Consider and Employee and Address relationship. There is a One-to-one mapping between Employee and Address. Following are models: @Entity @Table(…
hibernate query-optimization fetch one-to-oneI am developing a web application that can support threaded comments. I need the ability to rearrange the comments based …
performance database-design comments query-optimization table-structureI'm trying to understand physical plans on spark but I'm not understanding some parts because they seem different from traditional …
sql apache-spark query-optimization apache-spark-sql catalystI want to select records from '2013-04-01 00:00:00' to 'today' but, each day has lot of value, because …
php mysql sql query-optimization sql-optimizationI am running a query like: SELECT f.*, p.countryName, p.airportName, a.name AS agentName FROM ( SELECT f.outboundlegid, …
sql amazon-web-services query-optimization amazon-athena prestoIs there a way to optimize this further or should I just be satisfied that it takes 9 seconds to count 11…
sql mysql query-optimizationI have to delete about 10K rows from a table that has more than 100 million rows based on some criteria. …
mysql query-optimization sql-delete sql-execution-planI'm puzzled by the following. I have a DB with around 10 million rows, and (among other indices) on 1 column (campaignid_…
sql-server tsql query-optimization performance