commands for query in sql

Query commands in SQL are used to retrieve data from the database. The most commonly used command is SELECT, which obtains specific data from the table based on the WHERE condition. Other commonly used query commands include INSERT (insert new rows), UPDATE (update existing values), and DELETE (delete rows).

Commands used for query in SQL

In SQL (Structured Query Language), query commands are used for Retrieve data from the database. The most commonly used query command is SELECT, which is used to get specific rows and columns from a table.

SELECT command syntax:

<code>SELECT column1, column2, ...
FROM table_name
WHERE condition;</code>

Parameter description:

• ##column1, column2, .. .: The column name to be retrieved.
• table_name: The name of the table to be queried.
• WHERE condition: Optional condition for filtering results.

Other commonly used query commands:

INSERT: Insert new rows into the table.
UPDATE: Updates the value of an existing row in the table.
DELETE: Delete rows from the table.

Query command example:

Select the "name" and "age" columns from the "Students" table:

<code>SELECT name, age
FROM Students;</code>

Select all rows with a price greater than 100 from the "Orders" table:

<code>SELECT *
FROM Orders
WHERE price > 100;</code>

Insert a row into the "Students" table:

<code>INSERT INTO Students (name, age)
VALUES ('John Doe', 21);</code>

Update the price of a specific order in the "Orders" table:

<code>UPDATE Orders
SET price = 150
WHERE order_id = 1;</code>

Delete a specific product from the "Products" table:

<code>DELETE FROM Products
WHERE product_id = 10;</code>

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