Is SQL Case-Sensitive: A Look at Syntax, Tables, and Column Names?

Case sensitivity of SQL syntax

Contrary to popular belief, SQL syntax is not completely case-insensitive. Although keywords such as "SELECT", "FROM", and "WHERE" are always treated as uppercase, this is simply a convention.

Case sensitivity of table and column names

However, the case sensitivity of table and column names depends on the specific database system. MySQL provides a configuration option to control this behavior, and on Linux systems, names are case-sensitive by default. Instead, SQL Server case sensitivity is determined by the database's collation settings.

MySQL case sensitivity configuration

MySQL's lower_case_table_names server option determines whether table and column names are case-sensitive. If this option is set to 1, the name will be converted to lowercase, making it case-insensitive. To enable case sensitivity, set this option to 0.

Collation settings for SQL Server

In SQL Server, collations define character interpretation, including case comparisons. Collations can be case-sensitive or case-insensitive. The following options provide examples of case-sensitive and case-insensitive collations:

<code class="language-sql">区分大小写：SQL_Latin1_General_CP1_CI_AS
不区分大小写：SQL_Latin1_General_CP1_CS_AS</code>

Therefore, the case sensitivity of SQL syntax may be subtle, keywords are generally not case-sensitive, but table and column names may be case-sensitive, depending on the database system and configuration settings.

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