I have a question regarding filtering in MySQL. I have two tables one with members and one with membership data. I like to be able to join the two tables and be able to filter on:
Can anyone give me the correct SQL code the filter on this? I am not realy good in this more advanced SQL statements. Many thanks in advance!
Members
+----+------------+
| ID | Name |
+----+------------+
| 01 | Gerico |
| 02 | Stefan |
+----+------------+
Membership
+----+------------+-------------+------------+
| ID | MemberID | From | To |
+----+------------+-------------+------------+
| 01 | 01 | 01/01/1990 | 01/01/2000 |
| 02 | 01 | 01/01/2005 | 31/12/2154 |
| 03 | 02 | 01/01/1990 | 01/01/2000 |
| 04 | 02 | 01/01/1992 | 31/12/1999 |
+----+------------+-------------+------------+
I am assuming an active member is one who has a membership whose date range includes the current date. Then to select active members:
SELECT DISTINCT Members.* FROM
Members JOIN Membership ON Members.ID = Membership.MemberID
WHERE CURDATE() BETWEEN Membership.`From` AND Membership.`To`
(A SELECT DISTINCT
is done in case a member has multiple, overlapping memberships.)
Or you can use:
SELECT * FROM Members
WHERE EXISTS (
SELECT ID FROM Membership WHERE CURDATE() BETWEEN `From` AND `To` AND MemberID = Members.ID
)
To select non-active members:
SELECT * FROM Members
WHERE NOT EXISTS (
SELECT ID FROM Membership WHERE CURDATE() BETWEEN `From` AND `To` AND MemberID = Members.ID
)
The comment made by @Strawberry refers to the responsibility of the OP to create the above db-fiddle or equivalent for people to be able to test against us.
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