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This article mainly explains "how to modify the value of a column by mysql". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn "how to modify the value of a column by mysql".

Update statement can be used in mysql to modify the value of a column, the syntax "UPDATE table name SET field = new value;", you can modify the value of the specified column in all rows; if you only want to change the value of one row and one column, just add constraints, syntax "UPDATE table name SET field = new value WHERE condition;"

The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.

In MySQL, you can use UPDATE statements to modify the data of a table.

The syntax format is:

UPDATE table name SET field 1 = value 1 [, field 2 = value 2... ] [WHERE clause]

The syntax is as follows:

Table name: used to specify the table name to update.

SET clause: used to specify the column name to be modified in the table and its column value. Where each specified column value can be an expression or a default value for that column. If the default value is specified, the DEFAULT keyword is available to indicate the column value.

WHERE clause: optional. Used to limit the rows in the table to be modified. If not specified, all rows in the table are modified.

Note: when you modify multiple column values for a row of data, each value of the SET clause can be separated by a comma.

Mysql modifies the value of a specified column in all rows

Example: in the tb_courses_new table, update all rows with a course_grade field value of 4

UPDATE tb_courses_new SET course_grade=4

Use the WHERE statement to add constraints and modify only the values of one row and one column

Example: in the tb_courses table, update the record with a course_id value of 2 and change the course_grade field value to 3.5

UPDATE tb_courses_new SET course_grade=3.5 WHERE course_id=2

At this point, I believe you have a deeper understanding of "how to modify the value of a column by mysql". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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