Best way to query objects by pairs of values

Question

I am wondering what would be the most efficient way to query some objects by the pairs of values, for example:

public class pair{
    integer x;
    boolean y;
    <constructor...>
}
List<pair> pairs = new List<pair>();
pairs.add(new pair(2, true));
pairs.add(new pair(3, false));
pairs.add(new pair(4, true));

Now I would like to find all objects of type T where some field A = x and B = y for each pair from list. Is there some efficient way to do this, avoiding limits?

Answer 1

My first thougth was to create a dynamic query like this:

Select Id, Name 
From Object__c
Where ((field1__c = '1' AND field2__c = '2') OR (field1__c = '3' AND field2__c = '4') OR ... )

The code needed for that can look like the following:

String query = 'Select Id From Object__c Where (';
Integer counter = 1;
for(pair p : pairs){
    query += '(field1__c = \'' + p.x + '\' AND field2__c = ' + p.y + ') ';
    if(counter < pairs.size())
        query+= ' OR ';
    counter++;
}
query += ')';

The other way to do such queries (and I think it is an eleganter way) is to create a new formula field that concatenates two fields into the one sting and then just bind a list variable in the dynamic SOQL query.

Formula field generates a sing like this:

field1__c + '/' + field2__c

The apex code for the query generation:

list<string> str = new list<string>();
for(pair p : pairs){
    str.add(p.x + '/' + String.valueOf(p.y));
}
String query = 'Select Id From Object__c Where MyFormula__c = : str ';
List<Object__c> obj = Database.query(query);