Question

I want to create a below table if it doesn’t exists.

create table TEST (
                id number NOT NULL PRIMARY KEY,  
                url varchar(1000) NOT NULL,  
                urlHash varchar(255) NOT NULL,  
                contentHash varchar(255),  
                modDate varchar(30),  
                contentLocation varchar(100),  
                status integer,  
                lastCrawlDate varchar(30)) ;

So my questions is something like this-

Create Table TEST if doesn't exist

In the same way for sequence-

create sequence test_seq start with 1 increment by 1 nomaxvalue;

Something like this the query will be for sequence too-

Create sequence test_sequence if doesn't exist

Answer 1

You could do an anonymous PL/SQL block:

DECLARE
  t_count INTEGER;
  v_sql VARCHAR2(1000) := 'create table TEST (
            id number NOT NULL PRIMARY KEY,  
            url varchar(1000) NOT NULL,  
            urlHash varchar(255) NOT NULL,  
            contentHash varchar(255),  
            modDate varchar(30),  
            contentLocation varchar(100),  
            status integer,  
            lastCrawlDate varchar(30))';
BEGIN
  SELECT COUNT(*)
    INTO t_count
    FROM user_tables
   WHERE table_name = 'TEST';

  IF t_count = 0 THEN
    EXECUTE IMMEDIATE v_sql;
  END IF;
END;
/

Similarly, you can use USER_SEQUENCES to look for an existing sequence and adapt this to suit.