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Sometimes, the same record exists in the data table. When getting a record in a table, it is obviously more meaningful to obtain a unique record than to obtain a duplicate record. So about how to deal with duplicate data in mysql database, let's explain this problem.

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SQL handles duplicate data

Syntax:

The basic syntax for using the DISTINCT keyword to eliminate duplicate records is as follows:

SELECT DISTINCT column1, column2,.columnN

FROM table_name

WHERE [condition]

Consider the CUSTOMERS table, which is recorded as follows:

First, let's take a look at how the SELECT statement returns duplicate salary records:

Running the above statement results in the following result, where a record with a SALARY of 2000 occurs twice, that is, a duplicate record from the original data table:

Now, let's use the DISTINCT keyword in the above SELECT query and see what happens:

The above statement will produce the following result, which again and again does not have any duplicate entries:

That's what Macz editor recommended to you: "how does Mysql handle duplicate data?" The article, hope to help you, more tutorials, all in Macz!

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