When Should Backticks (`) Be Used in SQL Queries?

SQL Backticks (`): Usage and Best Practices

The backtick (`) character isn't part of standard SQL syntax. However, several database systems (DBMS) utilize it for escaping identifiers (column and table names).

Identifier Escaping

The SQL standard suggests using double quotes (") for identifier delimiters:

<code class="language-sql">SELECT "select" FROM "from" WHERE "where" = "group by";</code>

But MySQL, for instance, offers backticks as an alternative:

<code class="language-sql">SELECT `select` FROM `from` WHERE `where` = `group by`;</code>

Microsoft SQL Server employs square brackets ([]):

<code class="language-sql">SELECT [select] FROM [from] WHERE [where] = [group by];</code>

When Escaping is Necessary

Ideally, avoid identifier escaping. Quoting becomes necessary when:

• Identifier is a Reserved Word: The identifier matches a keyword in your specific SQL dialect.
• Database Migration: Moving code between DBMS where keywords might differ.

Case Sensitivity

Remember that escaped identifiers are case-sensitive. "from" and "FROM" usually represent distinct columns.

Further Considerations

• Certain DBMS, such as Informix, might allow keywords as identifiers under specific conditions.
• DBMS often have restrictions on quoting within certain contexts. Always refer to your DBMS's documentation for precise guidelines.

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