mysql创建索引

摘要: 创建索引

mysql

创建索引：ALTER TABLE appmobile.t_boss_workorder ADD INDEX idx_workorder_crmOrderid(crm_orderId);

删除索引：ALTER TABLE appmobile.t_boss_workorder DROP INDEX idx_workorder_crmOrderid;

检查sql的执行计划：EXPLAIN select t2.comments as comments,t2.id,t2.lastup_date from appmobile.t_boss_workorder t3 ,appmobile.t_boss_workitem t2
where t3.order_id = t2.order_id and
t3.crm_orderId = '234'
order by t2.lastup_date desc
limit 1

oracle创建索引：Create index PARTNER.IDX_PR_MEMBERCODE on PARTNER.PT_SEASHELL_DETAIL_FILTER(PR_MEMBERCODE) TABLESPACE PARTNER_IDX;
删除索引：drop index PARTNER.IDX_PR_MEMBERCODE;