SQL (Like /REGEXP_LIKE)

Question

Can you help me to write a query which returns emp_name with the first name matches with the value in reference table?
EmployeeTable_*
Id     Emp_Name
1     Mark Anthony
2     Issac Newton
3     Albert Einstein
4     Abraham Lincoln
ReferenceTable_*
First_Name
Mark
Albert
Output*
Id     Emp_Name
1     Mark Anthony
3     Albert Einstein
Can we use REGEXP_LIKE here?if yes, please tell me how the query should be.
Thanks
Ben

Answer 1

You can just join the tables with LIKE:
with emp as
    select 1 as id,     'MARK Anthony' as emp_name from dual union all
    select 2,   'Issac Newton' from dual union all
    select 3,   'Albert Einstein' from dual union all
    select 4,   'Abraham Lincoln' from dual union all
    select 5,   'Markus Aurelius Cesar' from dual
), ref as
   select 'Mark' as first_name from dual union all
   select 'Albert' from dual
select
emp.id,
emp.emp_name
from ref
join emp
on emp.emp_name like ref.first_name||'%';But the above will give you Markus Aurelius and not MARK Anthony.
So you could do it with REGEXP_LIKE:
with emp as
    select 1 as id,     'MARK Anthony' as emp_name from dual union all
    select 2,   'Issac Newton' from dual union all
    select 3,   'Albert Einstein' from dual union all
    select 4,   'Abraham Lincoln' from dual union all
    select 5,   'Markus Aurelius Cesar' from dual
), ref as
   select 'Mark' as first_name from dual union all
   select 'Albert' from dual
select
emp.id,
emp.emp_name
from ref
join emp
on regexp_like(emp.emp_name,'^'||ref.first_name||'([[:space:]]|$)','i')That regexp matches where emp_name begins with first_name followed by either some whitespace or the end of string. The 'i' makes the match case insensitive.