[tracker1]

How do you compare null, true, false, '', 'Y', 'True' in such a case, all are values that might wind up in a boolean field... though if you're using json-schema for your schemas, that's less of an issue in the common case.

IMHO anything that is to be queried against regularly should be normalized into an actual column.

[manigandham]

I'm not talking about the values, just the key names themselves... databases should be smart enough to realize that "username" and "id" and "timestamp" are keys repeated in most/every record and normalize them away so there isnt as big of a storage cost.