Keywords and user-defined identifiers that are used in an SPL program are case insensitive. For example, the statement DBMS_OUTPUT.PUT_LINE('Hello World'); is interpreted to mean the same thing as dbms_output.put_line('Hello World');, Dbms_Output.Put_Line('Hello World');, or DBMS_output.Put_line('Hello World');.

However, character and string constants, data retrieved from the PolarDB database compatible with Oracle, or data obtained from other external sources are case sensitive. The following output is generated by the DBMS_OUTPUT.PUT_LINE('Hello World!') ; statement:

Hello World!

However, the following output is generated by the DBMS_OUTPUT.PUT_LINE('HELLO WORLD!') ; statement:

HELLO WORLD!