I have a Postgres table that has numerous columns which frequently show up in the where clause of select queries. The table has been indexed accordingly, with indexes on all of these columns (mostly single-column indexes, but with some composite…
I have a very simple two-table set in Postgre 16.0: CREATE TABLE fk_table ( fk_id INT PRIMARY KEY , fk_name VARCHAR(50) ); CREATE TABLE main_table ( id INT PRIMARY KEY , date TIMESTAMP , fk INT REFERENCES fk_table(fk_id) --, tens…
When I select all columns, the indexing does not work, but if I select just a few columns, it does. mysql> explain SELECT * FROM fatura USE INDEX (datapago_serv_pago) WHERE id_servidor = 10 AND pago = '1' AND data_pago <=…
So I am very new to coding and have run into an issue when it comes to comparing arrays, especially ones that are nested and trying to pull out values that match using their indices into a new array. Say…
I'm working on an express.js project, using Sequelize as the orm, and postgres as the engine. I'm working on improving the performance of a slow select query that does many things, and one of them is comparing the acronym of…
When the query does not meet the conditions for index coverage,if Innodb will use index condition pushdown by auto? or how to explain these two thing by simple word or example.
I have a log table with timestamped (DATETIME) rows in the millions which I occasionally need to search by date or date range. I have an index on the timestamp column at present for the purpose. However, I am wondering…
I have 3 tables. country, team, player table Country id name 1 x 2 x 3 x table Team id name country_id 1 x 1 2 x 1 3 x 1 table Player id name country_id team_id 1 x 1…
I have a database table that having close to 100 columns - 25 columns are STRING, the rest is INT/DECIMAL/BOOL. This is the query that I am trying to run - the query is generated based on the search criteria…
CREATE TABLE `test` ( `id` bigint UNSIGNED NOT NULL AUTO_INCREMENT, `month` timestamp NOT NULL DEFAULT '2018-01-01 00:00:00', `b` varchar(255) NOT NULL DEFAULT '', `c` varchar(255) NOT NULL DEFAULT '', `d` varchar(255) NOT NULL DEFAULT '', `e` varchar(255) NOT NULL DEFAULT…