MySQL INSERT: VALUES vs. SET – What's the Real Difference?

MySQL INSERT statement: Detailed explanation of the differences between VALUES and SET

In database operations, two syntaxes are often used when inserting data: INSERT INTO table VALUES... and INSERT INTO table SET. Understanding the subtle differences between these two syntaxes can improve your SQL skills and optimize database interactions.

Grammar structure and equivalence

The syntax of the two statements is as follows:

• INSERT INTO table (column1, column2, ...) VALUES (...)
• INSERT INTO table SET column1 = value1, column2 = value2, ...

The

VALUES syntax conforms to the SQL standard, while the SET syntax is a MySQL-specific extension. Essentially, both statements accomplish the same goal: insert a new row into the table based on a specified value.

Performance impact

Contrary to popular belief, the performance of these two syntaxes is essentially the same. The MySQL documentation confirms this equivalence, stating that "both the INSERT ... VALUES and INSERT ... SET statement forms insert rows based on explicitly specified values" and have similar performance characteristics.

Additional instructions in the MySQL documentation

The MySQL documentation provides further instructions:

The difference between the SET and VALUES syntax forms is that the SET syntax allows you to insert values ​​into the table even if no column names are specified. When inserting data from a CSV file or other data source that does not provide column names This is very useful. ”

Example

To illustrate their equivalence, consider the following example:

<code class="language-sql">INSERT INTO table (a, b, c) VALUES (1, 2, 3)</code>

<code class="language-sql">INSERT INTO table SET a = 1, b = 2, c = 3</code>

Both statements will insert a row of new data into the "table" table, with the values ​​of columns a, b, and c being 1, 2, and 3 respectively.

Conclusion

Understanding the subtle differences between INSERT INTO table VALUES... and INSERT INTO table SET in MySQL allows developers to use these syntaxes interchangeably depending on their preference or specific use case. Performance results for both structures are identical, enabling efficient and optimized data insertion.

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