Backticks vs. Square Brackets in SQL: When to Use Which?

Distinguishing Between Backticks and Square Brackets in SQL

In SQL statements, backticks and square brackets serve similar purposes in enclosing field names, but with some key differences.

Backticks (MySQL)

MySQL employs backticks (``) for enclosing field names. They are primarily used to:

• Escape reserved names or characters that could conflict with SQL syntax.
• Distinguish between case-sensitive field names and keywords.

For example:

SELECT `username` FROM `users`

Square Brackets (SQL Server)

Unlike MySQL, SQL Server (and Microsoft Access) utilizes square brackets ([ ]) for field name enclosure. Their usage mimics that of backticks:

• Protecting reserved names or special characters.
• Differentiating between case-sensitive field names and keywords.

Example:

SELECT [username] FROM [users]

Compatibility and Usage Recommendations

• SQL Server: Use square brackets for field name enclosure.
• MySQL: Use backticks for field name enclosure, or double quotation marks if ANSI_QUOTES mode is enabled.

Note: Square brackets are not valid field name enclosures in MySQL, so it's important to adhere to the recommended syntax for the specific database you're using.

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