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How to unset a variable in MongoDB shell?
Use delete operator to unset variable in MongoDB shell. Following is the syntax −
delete yourVariableName;
Let us now implement the above syntax in order to unset variable in MongoDB shell. First, print the variable name −
> customerDetail;
This will produce the following output −
2019-05-08T22:29:17.361+0530 E QUERY [js] ReferenceError: customerDetail is not defined : @(shell):1:1
Now you can set a value in the above variable. Following is the query −
> customerDetail={"CustomerFirstName":"Chris"};
This will produce the following output −
{ "CustomerFirstName" : "Chris" }
Following is the query to show the value of a variable −
> customerDetail;
This will produce the following output −
{ "CustomerFirstName" : "Chris" }
Following is the query to unset a variable in MongoDB shell −
> delete customerDetail;
This will produce the following output −
true
Let us verify the variable exists or not. If it does not exist then you will get an error otherwise, a value −
> customerDetail;
This will produce the following output −
2019-05-08T22:30:35.530+0530 E QUERY [js] ReferenceError: customerDetail is not defined : @(shell):1:1
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