System Packages Oracle PLSQL

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SQL> exec dbms_output.put_line( dbms_random.string( 'A', 20 ) );
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PL/SQL procedure successfully completed.
SQL> exec dbms_output.put_line( dbms_random.string( 'x', 20 ) );
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PL/SQL procedure successfully completed.
SQL> exec dbms_output.put_line( dbms_random.string( 'P', 20 ) );
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PL/SQL procedure successfully completed.
SQL> exec dbms_output.put_line( dbms_random.string( 'l', 20 ) );
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PL/SQL procedure successfully completed.
SQL> exec dbms_output.put_line( dbms_random.string( 'u', 20 ) );
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PL/SQL procedure successfully completed.
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