Dynamically assigning variables based on condition in pl/sql

Question

I have a script which takes 6 input parameters but based on input 1 parameters 2 to 6 will be assigned to different variables. but the condition is not being checked during variable assignment phase. even if table_update is 'P' para,mater 2 is getting assigned to tariff_group instead of offer_id. Is there any way to solve this problem so that variables get assigned based on condition.
table_update := '&1';
if(table_update = 'T')
THEN
     tariff_group := '&2';
     gf_version := &3;
     tariff_table_name := '&4';
     flag := '&5';
     if(no_rows_tariff(tariff_table_name, gf_version, tariff_group))
     THEN
          if(flag = 'I')
          THEN
               tariff_column_name := column_tariff(tariff_table_name);
          ELSIF(flag = 'R')
          THEN
               max_gf_tariff(tariff_table_name, gf_version, tariff_group);
          ELSE
               DBMS_OUTPUT.PUT_LINE('Please enter correct option for update I- Insert R-Rollback');
          END IF;
     END IF;
ELSIF(table_update = 'P')
THEN
     offer_id := &2;
     gf_version := &3;
     promotion_table_name := '&4';
     flag := '&5';

Answer 1

Although you do not say what your problem is, I suspect that it si something like this:
SQL> !cat t.sql
DECLARE
   table_update         VARCHAR2(1);
   tariff_group         VARCHAR2(3);
   gf_version           NUMBER;
   tariff_table_name    VARCHAR2(5);
   offer_id             NUMBER;
   promotion_table_name VARCHAR2(5);
   flag                 VARCHAR2(1);
BEGIN
   table_update := '&1';
   IF table_update = 'T' THEN
      tariff_group := '&2';
      gf_version := &3;
      tariff_table_name := '&4';
      flag := '&5';
   ELSIF table_update = 'P' THEN
      offer_id := &2;
      gf_version := &3;
      promotion_table_name := '&4';
      flag := '&5';
   END IF;
   DBMS_OUTPUT.Put_Line ('TableUpdate: '||table_update);
   DBMS_OUTPUT.Put_Line ('TariffGroup: '||tariff_group);
   DBMS_OUTPUT.Put_Line ('GfVersion: '||gf_version);
   DBMS_OUTPUT.Put_Line ('Tarifftable: '||tariff_table_name);
   DBMS_OUTPUT.Put_Line ('OfferID: '||offer_id);
   DBMS_OUTPUT.Put_Line ('PromoTable: '||promotion_table_name);
END;
SQL> @t T TG1 1 TTN1 F
old  10:    table_update := '&1';
new  10:    table_update := 'T';
old  12:       tariff_group := '&2';
new  12:       tariff_group := 'TG1';
old  13:       gf_version := &3;
new  13:       gf_version := 1;
old  14:       tariff_table_name := '&4';
new  14:       tariff_table_name := 'TTN1';
old  15:       flag := '&5';
new  15:       flag := 'F';
old  17:       offer_id := &2;
new  17:       offer_id := TG1;
old  18:       gf_version := &3;
new  18:       gf_version := 1;
old  19:       promotion_table_name := '&4';
new  19:       promotion_table_name := 'TTN1';
old  20:       flag := '&5';
new  20:       flag := 'F';
      offer_id := TG1;
ERROR at line 17:
ORA-06550: line 17, column 19:
PLS-00201: identifier 'TG1' must be declared
ORA-06550: line 17, column 7:
PL/SQL: Statement ignoredAs you can see, the initial assignments for compilation purposes are done prior to actually running the code, and the assignment to offer_id is failing.
If I change offer_id to a varchar and quote the &2, then the compilation assignemnt works, and the actual logic of the script works:
SQL> !cat t.sql
DECLARE
   table_update         VARCHAR2(1);
   tariff_group         VARCHAR2(3);
   gf_version           NUMBER;
   tariff_table_name    VARCHAR2(5);
offer_id VARCHAR2(3);
   promotion_table_name VARCHAR2(5);
   flag                 VARCHAR2(1);
BEGIN
   table_update := '&1';
   IF table_update = 'T' THEN
      tariff_group := '&2';
      gf_version := &3;
      tariff_table_name := '&4';
      flag := '&5';
   ELSIF table_update = 'P' THEN
offer_id := '&2';
      gf_version := &3;
      promotion_table_name := '&4';
      flag := '&5';
   END IF;
   DBMS_OUTPUT.Put_Line ('TableUpdate: '||table_update);
   DBMS_OUTPUT.Put_Line ('TariffGroup: '||tariff_group);
   DBMS_OUTPUT.Put_Line ('GfVersion: '||gf_version);
   DBMS_OUTPUT.Put_Line ('Tarifftable: '||tariff_table_name);
   DBMS_OUTPUT.Put_Line ('OfferID: '||offer_id);
   DBMS_OUTPUT.Put_Line ('PromoTable: '||promotion_table_name);
END;
SQL> @t T TG1 1 TTN1 F
30  /
old  10:    table_update := '&1';
new  10:    table_update := 'T';
old  12:       tariff_group := '&2';
new  12:       tariff_group := 'TG1';
old  13:       gf_version := &3;
new  13:       gf_version := 1;
old  14:       tariff_table_name := '&4';
new  14:       tariff_table_name := 'TTN1';
old  15:       flag := '&5';
new  15:       flag := 'F';
old  17:       offer_id := '&2';
new  17:       offer_id := 'TG1';
old  18:       gf_version := &3;
new  18:       gf_version := 1;
old  19:       promotion_table_name := '&4';
new  19:       promotion_table_name := 'TTN1';
old  20:       flag := '&5';
new  20:       flag := 'F';
TableUpdate: T
TariffGroup: TG1
GfVersion: 1
Tarifftable: TTN1
OfferID:
PromoTable:John