匹配两个表中的记录

Question

I have two Tables: ads_info and ads.

I want to match records from two tables.

SQL Schema for ads:

| id |                 title |
|----|-----------------------|
|  1 | This Dog is very nice |

SQL Schema for ads_info:

| id |                     infotext |       tag |
|----|------------------------------|-----------|
|  1 | Dogs can eat a lot of things | dog, pets |

I want to check if the title of the Ads with id 1 has tags in ads_info. I have tried this:

SELECT * FROM `ads` where id = '1' UNION
SELECT * FROM `ads_info` where tag like '%ads.title%'

HERE IS SQL FIDDLE: LINK

Answer 1

Do you want a simple join ?

select a.*, ai.tag,
       (tag like concat('%', ads.title, '%')) as flag
from ads a join
     ads_info ai
     on ai.id = a.id;

The flag is, of course, false. It is rather hard to see situations where it would evaluate to true as you have expressed the logic.

Answer 2

Well you can do it this way: DEMO I am sure there are better ways and even this example can be better executed:) But it will maybe help...

First you create function for split and procedure for inserting those values in table(I have used here a answer from here LINK and corrected some small errors):

FUNCTION

CREATE FUNCTION SPLIT_STR(
  x VARCHAR(255),
  delim VARCHAR(12),
  pos INT
)
RETURNS VARCHAR(255)
RETURN REPLACE(SUBSTRING(SUBSTRING_INDEX(x, delim, pos),
       LENGTH(SUBSTRING_INDEX(x, delim, pos -1)) + 1),
       delim, '');

PROCEDURE

CREATE PROCEDURE ABC(in fullstr VARCHAR(255))

BEGIN

DECLARE a int default 0;
DECLARE str VARCHAR(255);

      simple_loop: LOOP
         SET a=a+1;
         SET str=SPLIT_STR(fullstr,",",a);
         IF str='' THEN
            LEAVE simple_loop;
         END IF;

         insert into my_temp_table values (str);
      END LOOP simple_loop;
END;

I have created a table for this values:

create table my_temp_table (temp_columns varchar(100));

Called the procedure:

 call ABC((select tag from ads_info));

And then you can use this:

Select * from ads B where exists
(select * from my_temp_table where 
find_in_set(UPPER(trim(temp_columns)), replace(UPPER(B.TITLE), ' ', ',')) > 0 );

Or this:

SELECT * FROM ads, my_temp_table
WHERE find_in_set(UPPER(trim(temp_columns)), replace(UPPER(ads.TITLE), ' ', ',')) > 0 ;