What is the difference between “replace into” and “replace” in MySQL?

In MySQL, REPLACE INTO and REPLACE are two different ways to replace data.

REPLACE INTO is a method of inserting new data into a table. If there is an existing primary key or unique index in the table, the operation will first delete the old data before inserting the new data. If there is no existing primary key or unique index, the new data will be inserted directly.

The REPLACE operation replaces data in a table. If there are duplicate primary keys or unique indexes in the table, it will first delete the old data before inserting the new data. If there are no duplicate primary keys or unique indexes in the table, it will insert the new data directly.

Therefore, the REPLACE INTO command will first delete the old data before inserting the new data, while REPLACE will directly replace the data. The difference between the two lies in their handling methods, so it is necessary to choose the appropriate operation based on the specific situation.