How do I go through a MySQL table in a database and add records using some information stored in existing records in that table?

The question is a little confusing but:

" I need a new Field_ID where the StringValue is the same as the Record_ID value from another row."

Would be something like this:

Select * from tablename where StringValue in (select Record_ID from tablename)

That would give you a list of rows where the string value is the same as a record_ID from any row.

You could then loop through them and update data to your liking.

is that what you needed?

Hello!
 the Field_ID column usually populated with a sequence. Sequence is an object in MySQL. When you create a table you can aasign a sequence toa column, so everytime you add a row into a table the column with sequence will be populated automatically with next number.
 In your case you need to fill in missed number which I'm not sure how to do without getting it VERY complicated.
 All I can help you with is to continue to add rows after the maximum Field_Id found.
Ex:
select max(Field_ID) from  
insert into   (field_ID, record_ID, string_value) select max(Field_ID), ,  from  


Kind regards,
t.

In addition to Anakinjay's post, what is the criteria for choosing what record_ID value to use for the new record? What guides the decision to add an existing record_ID as a new record?

Sorry for any confusion. What I meant was I need to create new rows, but in the new rows I need the value in the Field_ID column to be always be 10105, and for the values in StringValue and Record_ID to be equal to the value of a Record_ID value from another row already in the table.

The record_ID is just an increment of a number that is stored elsewhere in the database. Each time a new image is added, the number is incremented. Then we use that number in THIS table to assign additional information about it, like where the photo was taken, a description, file name etc.

(These always stay the same)

Field_ID = What it is.
10102 = Country
10104 = City
10207 = Original name of the image file.
10105 = Image ID# (for web searching by ID# rather than city, or country)

So this is what we have for example (there are actually over a 100,000 rows like this) in the table.

10102, 2989455, Spain
10104, 2989455, Madrid
10207, 2989455, madrid.jpg

10102, 2989456, France
10104, 2989456, Paris
10207, 2989456, image001.jpg

10102, 2989457, United Kingdom
10104, 2989457, London
10207, 2989457, city.jpg

I need to do this:

10102, 2989455, Spain
10104, 2989455, Madrid
10207, 2989455, madrid.jpg
10105, 2989455, 2989455

10102, 2989456, France
10104, 2989456, Paris
10207, 2989456, image001.jpg
10105, 2989456, 2989456

10102, 2989457, United Kingdom
10104, 2989457, London
10207, 2989457, city.jpg
10105, 2989456, 2989456

So these are going to be added to the table.

10105, 2989455, 2989455
10105, 2989456, 2989456
10105, 2989457, 2989457

Am I making better sense now?