Oracle 18c

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CREATE TABLE MyProject_COST (
        ID int NOT NULL UNIQUE,
        detail varchar2(25) NOT NULL,
        cost int CHECK(Cost >= 500)
    );
insert into MyProject_COST(id, detail, cost) values(1, 'foo', 0);
ORA-02290: check constraint (FIDDLE_XUVVCZVSYWWROHKPBFUF.SYS_C0030623) violated

declare
	c_name varchar2(255 char);
begin
	
	select c.constraint_name into c_name
	from all_constraints c
	join all_cons_columns cc 
		on  cc.table_name = c.table_name 
		and cc.constraint_name = c.constraint_name
	where 
		cc.table_name = 'MYPROJECT_COST' 
		and cc.column_name ='COST'
		and c.constraint_type = 'C' ;
	
	if c_name is not null then
		execute immediate 
		    'alter table myproject_cost drop constraint "' || c_name || '"';
	end if;
end;
/
1 rows affected

insert into MyProject_COST(id, detail, cost) values(1, 'foo', 0);
1 rows affected