plsql - Oracle, how to declare local variable inside executable block -


typically variables declared in declare section, , available inside begin block. find style stiff , tedious.

is possible declare variables inside begin block when needed? stupid declare new global variable, if it's needed store temporary value further calculations, queries , assertions.

try - added comments in code understand visibility domain of each variable. can remove comment last dbms_output see var2 no longer available in outer code.

set serveroutput on; <<tag>>         declare    var1 int := 1; -- global variable begin     declare       var1 int := 2; -- local variable      var2 int := 0;   begin         dbms_output.put_line(var1); -- display 2 (value of local var1);      dbms_output.put_line(tag.var1); -- display 1 (value of global var1);      dbms_output.put_line(var2); -- display 0 (value of local var2);   end;    dbms_output.put_line(var1); -- display 1 (value of global var1);   -- dbms_output.put_line(var2); -- crash since var2 no longer in memory; end;

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