mysql - Multiple inner join on a table where rows represent data attributes -


i have following user table (don't ask me why :) )

| id | cid | attr | text |   rdate    | --------------------------------------- |  1 |  1  | name |  joe |    null    | |  2 |  1  | date | null | 10.05.2014 | |  3 |  1  | stat |   2  |    null    | ---------------------------------------- |  4 |  2  | name |  joe |    null    | |  5 |  2  | date | null | 05.05.2014 | |  6 |  2  | stat |   1  |    null    | ---------------------------------------- |  7 |  3  | name |  joe |    null    | |  8 |  3  | date | null | 03.05.2014 | |  9 |  3  | stat |   2  |    null    |

as can see every user's attribute (name, date, stat) row in table. attributes same cid belong same user.

i delete entries refer user attribute date before 08.05.2014 , attribute stat not 2. after running query table be:

| id | cid | attr | text |   rdate    | --------------------------------------- |  1 |  1  | name |  joe |    null    | |  2 |  1  | date | null | 10.05.2014 | |  3 |  1  | stat |   2  |    null    | ---------------------------------------- |  7 |  3  | name |  joe |    null    | |  8 |  3  | date |  joe | 03.05.2014 | |  9 |  3  | stat |   2  |    null    |

is possible? inner join on same table?

group cid , use having clause run group functions check out requirements in every single group

delete your_table cid in (   select *    (     select cid     your_table     group cid     having sum(attr = 'date' , `date` < '2014-05-08') > 0     , sum(attr = 'stat' , `text` = 2) = 0   ) tmp_tbl )

in mysql can't delete same table selecting from. can trick mysql subquery in example above.


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