SQL> cl scr

SQL> declare
  2  i number:=1;
  3  begin
  4  loop
  5  exit when i>10;
  6  dbms_output.put_line(i);
  7  i=i+1;
  8  end loop;
  9  end;
 10  /
i=i+1;
 *
ERROR at line 7:
ORA-06550: line 7, column 2: 
PLS-00103: Encountered the symbol "=" when expecting one of the following: 
:= . ( @ % ; 
ORA-06550: line 8, column 1: 
PLS-00103: Encountered the symbol "END"  


SQL> declare
  2  i number:=1;
  3  begin
  4  loop
  5  exit when i>10;
  6  dbms_output.put_line(i);
  7  i:=i+1;
  8  end loop;
  9  end;
 10  /
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PL/SQL procedure successfully completed.

SQL> declare
  2  i number:=1;
  3  begin
  4  while i>10
  5  loop
  6  dbms_output.put_line(i);
  7  i:=i+1;
  8  end loop;
  9  end;
 10  /

PL/SQL procedure successfully completed.

SQL> declare
  2  i number:=1;
  3  begin
  4  loop
  5  exit when i<=10;
  6  loop
  7  dbms_output.put_line(i);
  8  i:=i+1;
  9  end loop;
 10  end;
 11  /
end;
   *
ERROR at line 10:
ORA-06550: line 10, column 4: 
PLS-00103: Encountered the symbol ";" when expecting one of the following: 
loop 


SQL> declare
  2  i number:=1;
  3  begin
  4  while i>10
  5  loop
  6  dbms_output.put_line(i);
  7  i:=i+1;/
  8  /
i:=i+1;/
       *
ERROR at line 7:
ORA-06550: line 7, column 8: 
PLS-00103: Encountered the symbol "/" when expecting one of the following: 
begin case declare end exit for goto if loop mod null pragma 
raise return select update while with <an identifier> 
<a double-quoted delimited-identifier> <a bind variable> << 
close current delete fetch lock insert open rollback 
savepoint set sql execute commit forall merge pipe 


SQL> declare
  2  i number:=1;
  3  begin
  4  while i<=10
  5  loop
  6  dbms_output.put_line(i);
  7  i:=i+1;
  8  end loop;
  9  end;
 10  /
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10                                                                              

PL/SQL procedure successfully completed.

SQL> declare
  2  i number;
  3  for i in 1..10 loop
  4  dbms_output.put_line(i);
  5  end loop;
  6  end;
  7  /
for i in 1..10 loop
*
ERROR at line 3:
ORA-06550: line 3, column 1: 
PLS-00103: Encountered the symbol "FOR" when expecting one of the following: 
begin function package pragma procedure subtype type use 
<an identifier> <a double-quoted delimited-identifier> form 
current cursor 
The symbol "begin" was substituted for "FOR" to continue. 


SQL> declare
  2  i number;
  3  begin
  4  for i in 1..10 loop
  5  dbms_output.put_line(i);
  6  end loop;
  7  end;
  8  /
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10                                                                              

PL/SQL procedure successfully completed.

SQL> declare
  2  i number;
  3  begin
  4  for i in reverse 1..10 loop
  5  dbms_output.put_line(i);
  6  end loop;
  7  end;
  8  /
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2                                                                               
1                                                                               

PL/SQL procedure successfully completed.

SQL> declare \
  2  /
declare \
        *
ERROR at line 1:
ORA-06550: line 1, column 9: 
PLS-00103: Encountered the symbol "\" when expecting one of the following: 
begin function package pragma procedure subtype type use 
<an identifier> <a double-quoted delimited-identifier> form 
current cursor 


SQL> declare
  2  i number;
  3  begin
  4  for i in 1..50 loop
  5  mod(i,2)=0 then
  6  /
mod(i,2)=0 then
        *
ERROR at line 5:
ORA-06550: line 5, column 9: 
PLS-00103: Encountered the symbol "=" when expecting one of the following: 
:= . ( % ; 


SQL> declare
  2  i number;
  3  begin
  4  for i in 1..50 loop
  5  if mod(i,2)=0 then
  6  dbms_output.put_line(i);
  7  end if;
  8  end loop;
  9  end;
 10  /
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PL/SQL procedure successfully completed.

SQL> spool off;