多个表结合在mysql中

Question

I have many tables in my server and they are name with the date. Example e_20150916 , e_20150917 , e_20150918 , e_20150919 .....etc

I want to do this table when user add date in my input type..... example when he wants the total summary between 2015/08/1 to 2015/08/15. Help me with these query how to do this.

I am doing this with 2 table combine.

Here my query for 2 tables

SELECT  e.cus,e.cusname,
        e.gid,
        SUM(total)
FROM ( 
    SELECT
        e.cus,
        e.cusname,
        e.gid,
        ROUND(SUM(TIMEDIFF(FROM_UNIXTIME(stoptime / 1000),
                        FROM_UNIXTIME(starttime / 1000))) / 60, 4) as total
    FROM
        e_cdr_$table
    WHERE e.cusname LIKE '%$customername%'
        UNION ALL
        SELECT
        e.cus,
        e.cusname,
        e.gid,
        ROUND(SUM(TIMEDIFF(FROM_UNIXTIME(stoptime / 1000),
                        FROM_UNIXTIME(starttime / 1000))) / 60, 4) as total
    FROM                                
        e_cdr_$table1
    WHERE e.cusname LIKE '%$customername%'
) s

I need to do this query for 7 tables. How can I do it?

Answer 1

As pointed out in the comments before, it is not the most clever approach to have a separate table for each date, but if that is the situation you need to live with you could at least do all the UNION ALL action in a sub query and then do the actual selection and SUM -magic with a single WHERE clause like:

SELECT  cus,cusname,gid,
        ROUND(SUM(TIMEDIFF(FROM_UNIXTIME(stoptime / 1000),
                    FROM_UNIXTIME(starttime / 1000))) / 60, 4) as total
FROM ( 
  SELECT * FROM e_20150916 UNION ALL
  SELECT * FROM e_20150917 UNION ALL
  SELECT * FROM e_20150918 UNION ALL
  SELECT * FROM e_20150919 UNION ALL
  SELECT * FROM e_20150920 UNION ALL
  SELECT * FROM e_20150921 UNION ALL
  SELECT * FROM e_20150922 ) tbls
WHERE cusname LIKE '%$customername%'
GROUP BY cus,cusname,gid

I am not sure about performance issues. If it should turn out that your tables are prohibitively large then you can of course limit their scope individually by doing:

SELECT  cus,cusname,gid,
        ROUND(SUM(TIMEDIFF(FROM_UNIXTIME(stoptime / 1000),
                    FROM_UNIXTIME(starttime / 1000))) / 60, 4) as total
FROM ( 
  SELECT * FROM e_20150916 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150917 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150918 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150919 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150920 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150921 WHERE cusname LIKE '%$customername%' UNION ALL
  SELECT * FROM e_20150922 WHERE cusname LIKE '%$customername%') tbls
GROUP BY cus,cusname,gid