When and Why Should I Use Backticks (`) in SQL Queries?

The use of backticks in SQL

When using MySQL and the mysql_query() function, be sure to put backticks around the table name to avoid errors. However, when using SQLite and C, backticks may not be recognized and may cause confusion.

The backtick character (`) is not defined by the SQL standard. Instead, it recommends using double quotes to separate identifiers as the standard quoting mechanism. For example:

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

In some dialects (e.g. MySQL), backticks can be used as a replacement for double quotes:

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

Other dialects (such as Microsoft SQL Server) may use square brackets for this purpose:

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

In general, it is recommended to avoid using quotes or backticks around identifiers whenever possible. This simplifies the code and ensures consistency. However, citations are required in the following cases:

• Identifiers are keywords reserved in specific SQL dialects.
• The identifier conflicts with a built-in function or object.
• Identifier contains special characters or spaces.

Use of quotation marks

It is important to note that the SQL standard specifies the use of single quotes (') to quote strings. Double quotes (") are an alternative used in some dialects, but their usage may vary. For example, in Oracle, double quotes are used to delimit identifiers, while in most other dialects they are used for strings .

Therefore, you must check the documentation for the specific SQL dialect you are using to determine the correct quoting conventions for strings and identifiers.

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