What are some of the common MySQL commands?

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MySQL is a popular open-source relational database management system, and it uses SQL (Structured Query Language) for managing and manipulating data. Here are some common MySQL commands:

  1. Logging into MySQL:

    code
    mysql -u username -p

    This command allows you to log into MySQL. Replace username with your MySQL username. You will be prompted to enter your password.

  2. Creating a Database:

    sql code
    CREATE DATABASE database_name;

    This command creates a new database with the specified name.

  3. Selecting a Database:

    code
    USE database_name;

    This command selects a specific database to work with.

  4. Creating a Table:

    sql code
    CREATETABLE table_name ( column1 datatype, column2 datatype, ... );

    This command creates a new table with specified columns and data types.

  5. Inserting Data:

    sql code
    INSERTINTO table_name (column1, column2, ...) VALUES (value1, value2, ...);

    This command inserts new rows of data into an existing table.

  6. Querying Data:

    sql code
    SELECT column1, column2, ... FROM table_name WHEREcondition;

    This command retrieves data from a table based on specified conditions.

  7. Updating Data:

    sql code
    UPDATE table_name SET column1 = value1, column2 = value2 WHEREcondition;

    This command modifies existing data in a table based on specified conditions.

  8. Deleting Data:

    sql code
    DELETEFROM table_name WHEREcondition;

    This command deletes data from a table based on specified conditions.

  9. Adding a New Column to a Table:

    sql code
    ALTERTABLE table_name ADD column_name datatype;

    This command adds a new column to an existing table.

  10. Modifying a Column in a Table:

    sql code
    ALTERTABLE table_name MODIFY column_name datatype;

    This command modifies the data type of an existing column in a table.

  11. Dropping a Table:

    sql code
    DROPTABLE table_name;

    This command deletes an existing table along with all its data.

  12. Dropping a Database:

    sql code
    DROP DATABASE database_name;

    This command deletes an existing database along with all its tables and data.

Remember that executing some of these commands can result in data loss, so always be cautious and make sure you have appropriate backups before making significant changes to your database.

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