Final answer:
SQL commands are used to perform various operations on the data stored in a database, such as retrieving data, inserting new data, updating existing data, and deleting data. Some commonly used SQL commands are SELECT, INSERT, UPDATE, and DELETE.
Step-by-step explanation:
SQL (Structured Query Language) is a programming language used to communicate with and manipulate databases.
SQL commands are used to perform various operations on the data stored in a database. Here are some commonly used SQL commands:
- The SELECT command is used to retrieve data from a database. It is used along with the FROM clause to specify the table(s) from which data is to be retrieved.
For example: SELECT column1, column2 FROM table_name;
- The INSERT command is used to insert new data into a table. It is used along with the VALUES clause to specify the values to be inserted.
For example: INSERT INTO table_name (column1, column2) VALUES (value1, value2);
- The UPDATE command is used to modify existing data in a table. It is used along with the SET clause to specify the new values.
For example: UPDATE table_name SET column1 = value1 WHERE condition;
- The DELETE command is used to delete existing data from a table. It is used along with the WHERE clause to specify the condition for deletion.
For example: DELETE FROM table_name WHERE condition;
These are just a few examples of SQL commands. There are many other commands available for different operations such as creating tables, altering tables, and more.