Database field data is not prepopulating

[Shah Baloch]

I integrated the Oracle database script runner to get data from two fields of the external database. I created two "Database Picker" custom field. I was having trouble to configure those field. Finally, I was able to configure it, but the problem is that data is not prepopulating. I have to Type complete customer id to get customer id, same has to type the first name to get name field data. I tried MySQL, it is working fine, where data get prepopulated like a drop-down or I just type one number/alphabet and can see the rest the data. My data is in Oracle so I have to use Oracle as an external database. 

Retrieval/validation Query for customer name field "select d, name_1 from customer where id = cast(? as VARCHAR2(255))"

Search SQL query for the customer name field "select id, (case when name_2 is not null then name_3 || ' ' || name_2 || ' ' || name_1 else name_3 || ' ' || name_1 end) as Fullname from customer where name_3 = cast(? as VARCHAR2(255))"

Retrieval/validation Query for the customer id field "select id, name_1 from customer where id = cast(? as VARCHAR2(100))"

Search SQL query for the customer id field "select name_3, id from customer and id = cast(? as VARCHAR2(100))"

For clarify, name_3, name_2, and name_1 are first, middle and last name 
What I'm doing wrong, can someone please help me, thank you!