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Like in MongoDB Query

In SQL, 'LIKE' query look like as below


In MongoDB it's look like as below(query in MongoDB console)


Same as

db.USERS.find({"FNAME":/^DILIP/})   // FNAME LIKE 'DILIP%'

db.USERS.find({"FNAME":/DILIP$/})   // FNAME LIKE '%DILIP'

$regex in MongoDB

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Add day to ISODate in MongoDB

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{ $add: [ <expression1>, <expression2>, ... ] }

Note:  If one of the argument is date $add operator treats to other arguments as milliseconds to add to the date.
Example: Suppose we have a Test collection as below.

{"Title" : "Add day to ISODate in MongoBD","CreatedDate" : ISODate("2016-07-07T08:00:00.000Z")}

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{ "_id" : ObjectId("579a1567ac1b3f3732483de0"), "Title" : "Add day to ISODate in MongoBD", "AddedDate" : ISODate("2016-07-09T08:00:00.000Z") }

Note: As mentioned in above note we have to convert days in millisecond because $add operator treat to other arg…

What is difference between UNION and UNION ALL in SQL Server

We use UNION and UNION ALL operator to combine multiple results set into one result set.
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Following some rules for using UNION/UNION ALL operator
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4.Column name of …