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  • mysql 库表整体相关查询

    select table_schema,table_name from information_schema.columns where column_name = '字段名';
    
    • 查询某张表有几条记录
    select count(*) FROM gasmis_shangxian.his_fuel_record;
    
    • 查询某几张表一个有多少条记录
    SELECT SUM(a) from(SELECT COUNT(*) a FROM gasmis_shangxian.his_fuel_record
    UNION
    SELECT COUNT(*)a FROM gasmis_shangxian.his_account_journal
    UNION
    SELECT COUNT(*) a FROM gasmis_shangxian.his_oilsys_fuel_record) as aa
    
    • 查询某个字段属于哪个库
    - > select table_schema,table_name from information_schema.columns where column_name = '字段名'
    
    
    • 批量更新某个主键,使其值增1,直接update会主键冲突,使用order by (神奇的order by 用法)
    UPDATE normalflow_list
    SET flow_seqno = flow_seqno + 1
    WHERE
    	flow_id = '010101'
    AND flow_seqno > 2
    ORDER BY
    	flow_seqno DESC;
    
    • 获取某一列的最大值

      select max(volumu) from table_name
      
      select max(flow_seqno) from normalflow_list where flow_id = '010101';
      
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  • 原文地址:https://www.cnblogs.com/sfth/p/11332532.html
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