Convert a varchar-type field to a field of type tinyint in MySQL

Because you didn't know the usage of the tinyint type before, you set some state attribute field types to varchar types, and then use "Yes" and "no" to determine the state

Later learned about the tinyint, want to try to use, but to convert the varchar type field to the tinyint type of field, explore the method as follows:

1. Change all the "yes" or "no" in the table to 0 because the current field type is varchar, so this step change is not a problem

2. Run the following SQL statement

ALTER table name MODIFY column name tinyint (1) DEFAULT 0;

In this way, the varchar type field is successfully changed to a field of type tinyint (where the length is set to 1)

As for the final location of each record to take 0 or 1, continue to do it

Convert a varchar-type field to a field of type tinyint in MySQL