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KodeCloud Databases

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  • In SQL all rows together form a table, multiple tables form a database and multiple database forms a server.
  • In NoSQL individual documents together form a collection, multiple collections form a database and multiple databases form a server.


  • Default data directory of MySQL is /var/lib/mysql
  • Default log location is /var/log/mysqld.log
  • When creating a user in MySQL in addition to username & password we also specify the location from which the user is allowed to connect to the Database.
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  • If we want to user to connect from any system then we specify it using the % system
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  • To restrict the actions of the user on different tables in a database we use grants.
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  • We can find mongodb logs at /var/log/mongodb/mongodb.log
  • Initially mongodb only listens on so we cannot access it from outside.
    • We have to change this in the conf file
  • We can change information like location where data is stored, log location, port etc in the /etc/mongod.conf
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  • Mongo shell usage
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Last updated: 2022-09-16