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MongoDB: How to query for records where field is null or not set?
... not there at all:
db.emails.count({sent_at: null})
Refer here for querying and null
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How to overload the operator++ in two different ways for postfix a++ and prefix ++a?
How to overload the operator++ in two different ways for postfix a++ and prefix ++a ?
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Convert.ToString(object o);
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How does OpenID authentication work?
... for user-centric digital identity. OpenID takes advantage of already existing internet technology (URI, HTTP, SSL, Diffie-Hellman) and realizes that people are already creating identities for themselves whether it be at their blog, photostream, profile page, etc. With OpenID you can easily transfor...