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In the last blog, there are three query condition to be described. In the blog, we will continue to what we have leant in the last blog. 

1 $mod 

'$mod' operation is able to make us to do simple mod operation, but is no need to use where sentence. 

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2. $ne, $in, $nin

‘$ne’ means not equal. '$in' is same as key word 'in' in relationship. $nin is opsitive to 'in'

3.$or and $nor 

durning the mutiple conditions, then result will be return that it only matches one condition among condition. 

as for $noe, which is in contrast with $no, let's learn it from the following the picture. 

4. $size

$size operation will query result whose size is equailvant to size of input.

5. $where 

6. $type