Sometimes we need to fetch data from three or more tables. There are two types available to do these types of joins. Suppose we have three tables named Student, Marks, and Details. Let’s say Student has (stud_id, name) columns, Marks has (school_id, stud_id, scores) columns, and Details has (school_id, address, email) columns. 1. Using SQL Join Clause This approach is similar to the way we join two tables. The following query returns result from three tables: SELECT name, scores, address,…

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We can connect two or more tables in MySQL using the JOIN clause. MySQL allows various types of JOIN clauses. These clauses connect multiple tables and return only those records that match the same value and property in all tables. The following are the four easy ways to join two or more tables in MySQL: Inner Join Left Join Right Join Cross Join

We can delete a row from the MySQL table using the DELETE STATEMENT within the database. The following is the generic syntax of DELETE statement in MySQL to remove one or more rows from a table: DELETE FROM table_name WHERE Condition_specified; It is noted that if we have not specified the WHERE clause with the syntax, this statement will remove all the records from the given table.

We can insert data in a MySQL table using the INSERT STATEMENT. This statement allows us to insert single or multiple rows into a table. The following is the basic syntax to insert a record into a table: INSERT INTO table_name ( field1, field2,…fieldN ) VALUES ( value1, value2,…valueN ); If we want to insert more than one rows into a table, use the below syntax: INSERT INTO table(field1, field2,…fieldN) VALUES (value1, value 2, …), (value1, value2, …), … (value1,…

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We can remove, drop, or delete one or more columns in an existing table using the ALTER TABLE statement as follows: ALTER TABLE table_name DROP COLUMN column_name1, column_name2….; To delete columns in MySQL, you would typically use the ALTER TABLE statement along with the DROP COLUMN clause. Here’s the syntax: ALTER TABLE table_name DROP COLUMN column_name; Replace table_name with the name of your table and column_name with the name of the column you want to delete. Make sure to execute…

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While creating a table, we have kept one of the column names incorrectly. To change or rename an existing column name in MySQL, we need to use the ALTER TABLE and CHANGE commands together. The following are the syntax used to rename a column in MySQL: ALTER TABLE table_name CHANGE COLUMN old_column_name new_column_name column_definition [FIRST|AFTER existing_column]; Suppose the column’s current name is S_ID, but we want to change this with a more appropriate title as Stud_ID. We will use the…

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Importing database in MySQL is a process of moving data from one place to another place. It is a very useful method for backing up essential data or transferring our data between different locations. For example, we have a contact book database, which is essential to keep it in a secure place. So we need to export it in a safe place, and whenever it lost from the original location, we can restore it using import options. In MySQL, we…

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Sometimes we need to change or rename the database name because of its non-meaningful name. To rename the database name, we need first to create a new database into the MySQL server. Next, MySQL provides the mysqldump shell command to create a dumped copy of the selected database and then import all the data into the newly created database. The following is the syntax of using mysqldump command: mysqldump -u username -p “password” -R oldDbName > oldDbName.sql Now, use the…

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Sometimes our table name is non-meaningful. In that case, we need to change or rename the table name. MySQL provides the following syntax to rename one or more tables in the current database: mysql> RENAME old_table TO new_table; If we want to change more than one table name, use the below syntax: RENAME TABLE old_tab1 TO new_tab1, old_tab2 TO new_tab2, old_tab3 TO new_tab3;

We can change the MySQL root password using the below statement in the new notepad file and save it with an appropriate name: ALTER USER ‘root’@’localhost’ IDENTIFIED BY ‘NewPassword’; Next, open a Command Prompt and navigate to the MySQL directory. Now, copy the following folder and paste it in our DOS command and press the Enter key. C:\Users\javatpoint> CD C:\Program Files\MySQL\MySQL Server 8.0\bin Next, enter this statement to change the password: mysqld –init-file=C:\\mysql-notepadfile.txt Finally, we can log into the MySQL…

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