Insert into select statement

The Insert into select statement is a SQL statement used to insert query results into the target table. It allows us to insert data from one table into another table while also performing any required transformations or filtering on the data. This syntactic structure is very useful when dealing with transformations and integrations between data sets.

#This syntax structure is very useful when dealing with conversion and integration between data sets. In the answer below, I will introduce the syntax, usage and examples of Insert into select statement in detail.

Syntax:

INSERT INTO 目标表名称 (目标列1, 目标列2, ...)
SELECT 列1, 列2, ...
FROM 源表名称
WHERE 条件;

Explanation:

Target table name: Indicates the name of the target table into which data is to be inserted.

Target column 1, target column 2, ...: Indicates the name of the target column of the target table into which data is to be inserted.

Source table name: Indicates the name of the source table from which data is selected.

Column 1, Column 2, ...: Indicates the name of the column to be selected.

WHERE condition: Optional, used to filter the data to be selected.

Purpose:

The main purpose of the Insert into select statement is to insert data from one table into another table. This can be used in many situations, including:

Copying data from one table to another.

Insert a specific column of one table into a specified column of another table.

Convert data from one table to the format of another table.

Select data from multiple source tables and insert them into a target table.

Example:

Suppose there are two tables: students and new_students. The students table contains students' names, ages, and grade information, and the new_students table is an empty table. We want to insert the names and grades of students aged 18 and above in the students table into the new_students table. You can use the Insert into select statement to accomplish this task.

INSERT INTO new_students (name, score)
SELECT name, score
FROM students
WHERE age >= 18;

The names and grades of students who are 18 years or older are inserted into the name and score columns of the new_students table.

Summary:

The Insert into select statement is a SQL statement used to insert query results into the target table. It can play a big role in the data conversion and integration process. We can use this statement to insert data from one table into another table and also perform any desired transformation or filtering on the data. The above example provides an application scenario of the Insert into select statement, I hope it will be helpful to you.

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