我使用的是PostgreSQL 9.2.9,它有以下問題。 有功能: CREATE OR REPLACE FUNCTION report_children_without_place(text, date, date, integer)
RETURNS TABLE (department_name character varying, kindergarten_name character va
最近我對Clojure很熟悉,我對懶惰序列評估的想法感到好笑,它只在必要時計算值。 我使用PostgreSQL數據庫工作了很多,並且在使用LIMIT子句時遇到了不同的查詢性能。例如查詢 SELECT * FROM(
SELECT id FROM foo1
INTERSECT
SELECT id FROM foo2) AS subquery
LIMIT 50
將具有
SELECT
business_period,
SUM(transaction.transaction_value) AS total_transaction_value,
SUM(transaction.loss_value) AS total_loss_value,
(total_transaction_value - total_loss_value) AS net_value
F
爲PostgreSQL調整以下SQL的最佳方式是什麼?這似乎代價很高?將創建臨時表提供最佳的成本? UPDATE table1
SET id = qry.crmId
FROM (
SELECT b.id AS crmId, a.row
FROM table1 AS a INNER JOIN table2 AS b ON lower(a.email) = lower(b.ema