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原创 mysql性能优化
【性能提升神器】STRAIGHT_JOIN 今天给大家下另一个性能提升神器-STRAIGHT_JOIN,在数据量大的联表查询中灵活运用的话,能大大缩短查询时间。 首先来解释下STRAIGHT_JOIN到底是用做什么的: STRAIGHT_JOIN is similar to JOIN, except that the left table is always read before the right table. This can be used for those (few) cases for whi
2021-12-15 21:46:17 45
原创 mysql查询所有父节点和子节点
SELECT * FROM qx_area WHERE (FIND_IN_SET(id,‘130100,140000’) OR FIND_IN_SET( 130100, parent_ids ) OR FIND_IN_SET( 140000, parent_ids ) OR FIND_IN_SET(id,( SELECT GROUP_CONCAT(parent_ids) FROM qx_area WHERE FIND_IN_SET(id,‘130100,140000’))) )
2021-11-30 15:50:13 366
原创 Java发送文件
public static void main(String[] args) { DataOutputStream out = null; final String newLine = "\r\n"; final String prefix = "--"; try { String url1= // “”; URL url = new URL(url1); HttpURLConnection conn = (HttpURLConnection)url.openConnecti
2021-11-25 11:01:49 256
原创 mysql删除重复数据
DELETE FROM qx_site_weather_hour WHERE id IN ( SELECT m.id FROM ( SELECT id FROM qx_site_weather_hour A, ( SELECT site_id, date_time FROM qx_site_weather_hour GROUP BY site_id, date_time HAVING COUNT() > 1 ) B WHERE A.site_id = B.site_id AND A.date_time
2021-11-23 11:00:03 1621
feign-slf4j-9.5.0.jar
2019-06-20
feign-core-9.5.0.jar
2019-06-20
jQuery EasyUI 1.4.1 版 API 中文
2016-08-13
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