Determine pHash similarity score

I am looking for a guy who can do the following easy job: I have 2 mysql tables containing data. Table 1: Column 1: ID Column 2: Mexican hat phash value of an image Table 2: Column 1: image_id (equal to ID in table 1) Column 2: Mexican hat phash value of an image I now need a script that does the following: - For each row in table 2, that does not have a value in the column "similarity" right now, the pHash similarity score of the Mexican hat phash value of the data row of table 2 and the value of the image of table 1 with the same id / image_id is calculated and then output in the column "similarity" in table 2. I need a fast solution for that!