Are PostgreSQL column names case-sensitive?
Whether PostgreSQL column names are case-sensitive depends on whether the column name is enclosed in double quotes. Normally, column names that are not enclosed in double quotes are converted to lowercase. This means that the column name "first_Name"
will be treated as "first_name"
by PostgreSQL.
However, if you enclose the column name in double quotes, the case of the letters will be preserved. This means that column names "first_name"
and "First_Name"
will be treated as different columns.
To solve this specific problem, you can surround the column names with double quotes, so the query becomes:
select * from persons where "first_Name"='xyz';
This should return the expected results.
It is important to note that values in the WHERE clause (for example: 'xyz'
) should also be enclosed in single quotes to represent string literals. This ensures that it cannot be misinterpreted as a column name.
Best practice is to recommend using lowercase column names and enclosing them in double quotes to avoid any potential case-related issues.
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