mysql中where后left,使用WHERE子句的MySQL LEFT JOIN查询

Hope someone can help as I am having a hard time understanding how to query properly

I have a Member table and a Member_Card table. Member_Card has a column Member, so the card is associated to a member. Both tables have a LastModifiedDate column. A member can have none, one or several cards.

I need to return all members whose LastModifiedDate >= sinceDate (given date) OR whose card (if any) LastModifiedDate >= sinceDate.

Imagine sinceDate is 2013-01-01 00:00:00. I want to output something like this:

[{

"Id": "001O000000FsAs7IAF",

"LastModifiedDate": 2013-01-01 00:00:00,

"Member_Card": null

}, {

"Id": "001O000000FrpIXIAZ",

"LastModifiedDate": 2012-12-12 00:00:00,

"Member_Card": [{

"Id": "