PL/SQL Script Line with Only a Dot...What is the purpose/function of the dot?
A line with only a dot, ".", appears to be a SQL*Plus command to end the input and save it in the buffer without executing it. 

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SQL&gt; DECLARE
  2     qty1 number;
  3  BEGIN
  4     select count(*) into qty1 from dba_roles;
  5     dbms_output.put_line('Number of roles: '||to_char(qty1));
  6  END;
  7  .
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SQL&gt; LIST
  1  DECLARE
  2     qty1 number;
  3  BEGIN
  4     select count(*) into qty1 from dba_roles;
  5     dbms_output.put_line('Number of roles: '||to_char(qty1));
  6* END;
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SQL&gt; DECLARE
  2     qty2 number;
  3  BEGIN
  4     select count(*) into qty2 from dba_procedures;
  5     dbms_output.put_line('Number of procedures: '||to_char(qty2));
  6  END;
  7  .
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SQL&gt; LIST
  1  DECLARE
  2     qty2 number;
  3  BEGIN
  4     select count(*) into qty2 from dba_procedures;
  5     dbms_output.put_line('Number of procedures: '||to_char(qty2));
  6* END;
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SQL&gt; /
Number of procedures: 26744

PL/SQL procedure successfully completed.

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