How to say… match when field is a number… in mongodb?

Question

So I have a field called \'city\' in my results...the results are corrupted, some times it\'s an actual name, sometimes it\'s a number. The following code displays all the recor

Answer 1

An easier way to match all docs where city is a numeric string is using the property '0' <= city <= '9' i.e. your aggregation query becomes:

db.zips.aggregate([
    {$project : {city:{$substr:["$city",0,1]}}},
    {$sort : {city : 1}}, 
    {$match: {city: {$gte: '0', $lte: '9'}}}
]);

When using JohnnyHK's suggestion of a regex you can save yourself the $project stage altogether.