Querying from Multiple Objects

Question

I've to Query a field(e.g X) from one object. Say I'm getting 20 records(LIST)

Now, I've to Query another object using result of above Query using field X (X field is common to both objects but has different names, say here Field1 and Field2) What is the easiest way to get data in Developer console ? is below correct

List<string> TP; 
List<ObjA > Ds1=  [Select id, name , TPID__C  
    from QRS_Quote_LOC_Plan_Bundle__c 
    where Field3 = '1111']; // Field3 is some another field

For(ObjA  b : Ds1 )
 TP.add(b.Field1); // storing common field data

List<ObjB> MasterD = [Select id, name from ObjB where Field2 in :TP ];
System.debug(MasterD );

Answer 1

You could use Relationship SOQL Queries. First you need to determine what type of relationship the two objects have child-to-parent relationship or vice-versa:

Child-to-parent

SELECT Id, Name, Widget__r.Id, Widget__r.Name
FROM Model__c
WHERE Widget__r.Name LIKE 'Ring%'

Parent-to-child

SELECT Name,
  (
    SELECT Name
    FROM Models__r
  )
FROM Widget__c

You can see more details here