How to write the latest tutorial on SQL insertion statement

The SQL INSERT statement is used to add new rows to a database table, and its syntax is: INSERT INTO table_name (column1, column2, ..., columnN) VALUES (value1, value2, ..., valueN);. This statement supports inserting multiple values ​​and allows NULL values ​​to be inserted into columns, but it is necessary to ensure that the inserted values ​​are compatible with the column's data type to avoid violating uniqueness constraints.

SQL Insert Statement

In SQL, the INSERT statement is used to add new rows to the database table. The syntax is as follows:

 <code class="sql">INSERT INTO table_name (column1, column2, ..., columnN) VALUES (value1, value2, ..., valueN);</code>

in:

• table_name : Specifies the table name to insert data.
• column1 , column2 , ..., columnN : Specifies the column name to insert the value.
• value1 , value2 , ..., valueN : Specifies the value to be inserted.

Example

Insert a row of data into a table named customers :

 <code class="sql">INSERT INTO customers (name, email, phone) VALUES ('John Doe', 'john.doe@example.com', '555-1212');</code>

Insert multiple values

If you want to insert multiple values ​​into a table, you can use the following syntax:

 <code class="sql">INSERT INTO table_name (column1, column2, ..., columnN) VALUES (value1, value2, ..., valueN), (value1, value2, ..., valueN), ..., (value1, value2, ..., valueN);</code>

Insert NULL value

To insert a NULL value into a column, you can use the NULL keyword:

 <code class="sql">INSERT INTO table_name (name, email, phone) VALUES ('John Doe', NULL, '555-1212');</code>

Notice:

• Make sure the value to be inserted is compatible with the column's data type.
• If you want to insert a self-increment column, exclude the column name from the insert statement.
• Verify uniqueness before inserting data into the primary key column to avoid violating uniqueness constraints.

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