Simple PL/SQL to check if table exists is not working - sql

Question

I'm in the process of converting some stored procedures from Sybase TSQL to Oracle PL/SQL and I've already come across a problem which I'm struggling to resolve!
The below code will not run:
DECLARE
t INT := 0;
t_error EXCEPTION;
v_line VARCHAR2(100);
BEGIN
SELECT COUNT(*) INTO t FROM user_tables WHERE table_name = UPPER('tbl_BSUK_PriceIssue');
IF t = 1 THEN
EXECUTE IMMEDIATE 'DROP TABLE tbl_BSUK_PriceIssue';
t := 0;
SELECT COUNT(*) INTO t FROM user_tables WHERE table_name = UPPER('tbl_BSUK_PriceIssue');
IF t = 1 THEN
RAISE t_error;
END IF;
END IF;
EXCEPTION
WHEN t_error THEN
v_line := '<<< FAILED DROPPING table tbl_BSUK_PriceIssue >>>';
dbms_output.put_line (v_line);
WHEN OTHERS THEN
v_line := '<<< Unknown Error >>>';
dbms_output.put_line (v_line);
END;
END;
I get the following error message, what am I doing wrong?!
Error starting at line : 17 in command - DECLARE
t INT := 0; t_error EXCEPTION; v_line VARCHAR2(100);
BEGIN
SELECT COUNT(*) INTO t FROM user_tables WHERE table_name =
UPPER('tbl_BSUK_PriceIssue');
IF t = 1 THEN EXECUTE IMMEDIATE 'DROP TABLE tbl_BSUK_PriceIssue';
t := 0; SELECT COUNT(*) INTO t FROM user_tables WHERE table_name =
UPPER('tbl_BSUK_PriceIssue'); IF t = 1 THEN
RAISE t_error; END IF; END IF;
EXCEPTION WHEN t_error THEN v_line := '<<< FAILED DROPPING table
tbl_BSUK_PriceIssue >>>'; dbms_output.put_line (v_line); WHEN
OTHERS THEN
v_line := '<<< Unknown Error >>>';
dbms_output.put_line (v_line); END;
END; Error report - ORA-06550: line 30, column 1: PLS-00103: Encountered the symbol "END"
06550. 00000 - "line %s, column %s:\n%s"
*Cause: Usually a PL/SQL compilation error.
*Action:
I'm actually trying to replace the following TSQL with a PL/SQL version:
-- Create temp table for relevant trev_id's
IF OBJECT_ID('dbo.tbl_BSUK_PriceIssue') IS NOT NULL
BEGIN
DROP TABLE dbo.tbl_BSUK_PriceIssue
IF OBJECT_ID('dbo.tbl_BSUK_PriceIssue') IS NOT NULL
PRINT '<<< FAILED DROPPING TABLE dbo.tbl_BSUK_PriceIssue >>>'
ELSE
PRINT '<<< DROPPED TABLE dbo.tbl_BSUK_PriceIssue >>>'
END
go

Answer 1

try to remove END; in this section
WHEN OTHERS THEN
v_line := '<<< Unknown Error >>>';
dbms_output.put_line (v_line);
END;
UPD. Actually, you can do it a bit shorter, no need to check if table exists after drop
declare
eTableNotExists exception;
pragma exception_init(eTableNotExists, -00942);
begin
EXECUTE IMMEDIATE 'DROP TABLE tbl_BSUK_PriceIssue';
dbms_output.put_line('<<< DROPPED TABLE dbo.tbl_BSUK_PriceIssue >>>');
exception
when eTableNotExists then null
when others then
dbms_output.put_line ('<<< Unknown Error >>>' || sqlerrm);
end;
/

Answer 2

I don't know about the error, but you can do what you want in a fraction of the code. You don't need the count variable if you use EXISTS() and you don't need EXECUTE IMMEDIATE because you don't have variable data in the command:
IF 1 = (SELECT 1 FROM user_tables WHERE table_name = 'TBL_BSUK_PRICEISSUE') THEN
DROP TABLE tbl_BSUK_PriceIssue;
IF 1 = (SELECT 1 FROM user_tables WHERE table_name = 'TBL_BSUK_PRICEISSUE') THEN
RAISE EXCEPTION;
END IF;
END IF;