Is SQL Case-Sensitive: How Do Different Database Systems Handle it?

Case sensitivity in SQL syntax

In the field of database management systems, the case sensitivity of SQL syntax has always been a topic of discussion. This article delves into the complexities of SQL case sensitivity and examines how it is handled on different database platforms.

The standard SQL specification states that keywords such as "SELECT", "FROM", and "WHERE" are not case-sensitive. This means they can be written using any combination of upper and lower case without affecting the functionality of the query. However, table and column names depend on the configuration of the underlying database system.

MySQL and SQL Server, two popular database platforms, handle case sensitivity differently. By default, MySQL treats table and column names as case-insensitive, allowing users to refer to them freely regardless of letter case. This behavior can be modified via a configuration option called "lower_case_table_names".

SQL Server, on the other hand, uses the concept of collation to define case sensitivity. Collation rules determine the rules for comparing and sorting characters. By default, a case-insensitive collation is used, making table and column names case-insensitive. However, users can define custom collations that enforce case sensitivity, requiring object names to match exactly.

In summary, while the standard SQL specification states that keywords are not case-sensitive, how table and column names are handled depends on the database platform and its configuration. MySQL typically provides case-insensitive handling, while SQL Server enables case sensitivity through collation settings. Database administrators should be aware of these differences to ensure consistent usage and efficient query performance.

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