Single vs. Double Quotes in SQL: When Should I Use Which?

The difference between SQL single quotes and double quotes

In SQL, single quotes are used to enclose strings to represent their literal values. Unlike many other programming languages ​​that use double quotes, SQL generally does not recognize double quotes.

Main differences:

• Single quotes: is used to represent strings and is required.
• Double quotes: is not usually used by SQL.

Use of single quotes:

• Enclose string literals: 'This is a string'
• Column alias: SELECT column_name AS 'alias'

Example:

<code class="language-sql">SELECT product_name AS '产品名称'
FROM Products;</code>

Other instructions:

• Some specific database implementations may support double quotes, but this is not standard usage.
• Single quotes are required when column aliases contain spaces, but this is not recommended.
• For consistency and best practice, it is recommended to always use single quotes around strings in SQL.

The above is the detailed content of Single vs. Double Quotes in SQL: When Should I Use Which?. For more information, please follow other related articles on the PHP Chinese website!