mongo quries
(base) Hemalakshmis-MacBook-Pro:~ hemalakshmi$ export PATH=$PATH:/Users/hemalakshmi/mongodb-macos-x86_64-enterprise-4.2.6/bin
(base) Hemalakshmis-MacBook-Pro:~ hemalakshmi$ ./mongo --nodb
-bash: ./mongo: No such file or directory
(base) Hemalakshmis-MacBook-Pro:~ hemalakshmi$ mongo --nodb
MongoDB shell version v4.2.6
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