Change/replace the value of a variable dynamically- oracle - sql

Question

I have set of sql statements (create table, views, sequences), Where my schema name changes all the time and rest of the sql be the same.
Even in schema name a part of it has to change, for example:
I have a schema name ABC_XYZ, i would like to change this schema name to ABC_DEF_XYZ.
For this i tried to insert a variable in the schema name like ABC_&var1_XYZ. If i pass the variable in the schema name as shown here (ABC_&var1_XYZ) and pass the value to the variable, It ask me to declare the vaue of the variable.
I have given the error and the code i use below:
Error report -
ORA-06550: line 5, column 52:
PLS-00201: identifier 'REL4' must be declared
ORA-06550: line 5, column 1:
PL/SQL: Statement ignored
ORA-06550: line 7, column 51:
PLS-00201: identifier 'REL4' must be declared
here is my create statement:
set echo off
set verify off
undefine mySchemaPart
declare
vSQL varchar2(32767);
begin
vSQL:= 'begin EXECUTE IMMEDIATE alter table ABC_'||&&mySchemaPart||'_OWNER.TEST drop constraint EMPLOYEE_ID_FK; EXCEPTION when others then if (SQLCODE != -02443 and SQLCODE != -942) then RAISE; end if; end';
execute immediate vSQL;
vSQL:= 'begin EXECUTE IMMEDIATE drop table ABC_'||&mySchemaPart||'_OWNER.TEST cascade constraints PURGE; EXCEPTION when others then if SQLCODE != -942 then RAISE; end if; end';
execute immediate vSQL;
vSQL:= 'create table ABC_'||&mySchemaPart||'OWNER.TEST
(
EMPLOYEE_ID NUMBER(19) not null,
LAST_UPDT_DT DATE not null,
)';
execute immediate vSQL;
vSQL:= 'CREATE OR REPLACE SYNONYM ABC_USER.TEST FOR ABC_'||&mySchemaPart||'OWNER.TEST';
execute immediate vSQL;
vSQL:= 'begin EXECUTE IMMEDIATE alter table ABC_'||&mySchemaPart||'OWNER.TEST
add constraint EMPLOYEE_ID_FK foreign key (EMPLOYEE_ID)
references ABC_OWNER.GDSD (EMPLOYEE_ID); EXCEPTION when others then if (SQLCODE != -02443 and SQLCODE != -02275) then RAISE; end if; end';
execute immediate vSQL;
end;
/
Is there any other way i can try to insert my value in this schema.

Answer 1

You can use dynamic SQL to handle a varying schema in your DDL; for example:
accept mySchemaPart PROMPT "Schema part: "
declare
vMySchema varchar2(30) := 'ABC_' || '&mySchemaPart' || '_XYZ';
vSQL varchar2(32767);
begin
vSQL := 'create table ' || vMySchema || '.tableName (...)';
execute immediate vSQL;
end;
/

Answer 2

Pass it as 'ABC_||'&var1||'_XYZ'
An example of insert statement;
insert into test (a)
select 'ABC_'||&var1||'_XYZ' from dual ;
On execution it will ask for prompt.
As a block you can use this:
declare
var varchar2(100);
begin
var:='create table ABC_'||&var1||'_XYZ.tablnam(a number)'; --add your columns
dbms_output.put_line(var);
execute immediate var;
end;
As per #bin request his/her statments:
declare
var varchar2(500);
begin
var:='create table ABC_'||&var||'_OWNER.TEST(EMPLOYEE_ID NUMBER(19) not null, LAST_UPDT_DT DATE not null )';
--Table Created
dbms_output.put_line(var);
execute immediate var;
var:='alter table ABC_'||&var1||'_OWNER.TEST add constraint EMPLOYEE_ID_FK foreign key (EMPLOYEE_ID) references ABC_OWNER.GDSD(EMPLOYEE_ID)';
--Constraint Added
dbms_output.put_line(var);
execute immediate var;
var:='CREATE OR REPLACE SYNONYM ABC_USER.TEST FOR ABC_'||&var1||'_OWNER.TEST';
--Synonym Created
dbms_output.put_line(var);
execute immediate var;
var:='alter table ABC_'||&var1||'_OWNER.TEST drop constraint EMPLOYEE_ID_FK';
--Constraint Dropped
dbms_output.put_line(var);
execute immediate var;
var:='drop table ABC_'||&var1||'_OWNER.TEST cascade constraints PURGE';
--Table Dropped
dbms_output.put_line(var);
execute immediate var;
Exception
WHEN others then
dbms_output.put_line('Error--'||sqlerrm||'-'||sqlcode);
end;
Output:
SQL> declare
var varchar2(100);
begin
var:='create table ABC_'||&var1||'OWNER.TEST(EMPLOYEE_ID NUMBER(19) not null, LAST_UPDT_DT DATE not null )';
'
'
'
dbms_output.put_line(var);
execute immediate var;
end;
Enter value for var1: 'REL4'
create table ABC_REL4_OWNER.TEST(EMPLOYEE_ID NUMBER(19) not null, LAST_UPDT_DT DATE not null )
Table created.
alter table ABC_REL4_OWNER.TEST add constraint EMPLOYEE_ID_FK foreign key (EMPLOYEE_ID) references ABC_OWNER.GDSD(EMPLOYEE_ID)
Table altered.
CREATE OR REPLACE SYNONYM ABC_USER.TEST FOR ABC_REL4_OWNER.TEST
Synonym created.
alter table ABC_REL4_OWNER.TEST drop constraint EMPLOYEE_ID_FK
Table altered.
drop table ABC_REL4_OWNER.TEST cascade constraints PURGE
Table dropped.