Question

I have the following data structure:

TABLE requirements
ID 1, AGE 1, GENDER 1, USERID 1
ID 2, AGE 1, GENDER 2, USERID 2
ID 3, AGE 1, GENDER 2, USERID 3


TABLE offers
IDoffers 1, AGE 1, GENDER 2, USERID 1
IDoffers 2, AGE 1, GENDER 1, USERID 2
IDoffers 3, AGE 1, GENDER 1, USERID 3

I need to select the row of the table requirements – The parameters of this line used to select data from a table offers. In the cycle.

SELECT * FROM offers WHERE (ID1 … IDX from requirements)

I need this result:

FOR ID 1 FROM TABLE requirements - RESULT FROM offers:
IDoffers 2, AGE 1, GENDER 1, USERID 2
IDoffers 3, AGE 1, GENDER 1, USERID 3

FOR ID 2 FROM TABLE requirements - RESULT FROM offers:
IDoffers 1, AGE 1, GENDER 2, USERID 1

FOR ID 3 FROM TABLE requirements - RESULT FROM offers:
IDoffers 1, AGE 1, GENDER 2, USERID 1

Answer 1

SELECT
  rquirements.ID,
  offers.*
FROM
  requirements
  INNER JOIN offers ON requirements.AGE=offers.AGE
     AND requirements.GENDER=offers.GENDER

Cycles through all requirements. If you want hust a special requirement, add

WHERE rquirements.ID=<whatever>