When to Use Backticks vs. Single Quotes in MySQL Queries: A Guide to Identifiers and String Literals

Understanding the Distinction between Backtick and Single Quote, and Query Implementation with IF Statements

In the context of MySQL, the distinction between the use of backticks (`) and single quotes (') is crucial. Backticks serve the purpose of quoting identifiers such as names of columns or tables, effectively shielding them from special interpretation. On the other hand, single quotes are employed for delineating string literals. Ignoring the distinction can result in syntax errors, as illustrated by the example:

SELECT select FROM foo

Here, the use of select without backticks, which typically represents a reserved keyword like GROUP BY, raises a syntax error. By employing backticks, as seen below, we rectifying the issue:

SELECT `select` FROM foo

Furthermore, the IF function can be utilized within query statements as a column specification. Its syntax resembles the following:

IF(predicate, expression1, expression2)

Returning to the example provided:

SELECT slug, type, IF(`value` = "", `default`, `value`) AS `value`, FALSE

Here, the IF function is employed to assess whether the value is an empty string (""). If so, it substitutes a default value in its place. Otherwise, the original value is retained. The resulting column is named value.

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