MySQL the whole query fails if result of sub query is NULL

Question

I have a situation where I need to generate rows with random data out of the same table's valid data

I have generated ID by php rand($min, $max) function with $min = 1 and $max = [SELECT MAX(ID) FROM patient] - 1

Select

tblFirstName.FirstName,
tblLastName.LastName,
tblBirthDate.BirthDate,
tblLocation.Location

From

(SELECT FirstName FROM patient WHERE ID > 11445 AND FirstName != '' LIMIT 1) AS tblFirstName,
(SELECT LastName FROM patient WHERE ID > 74964 AND LastName != '' LIMIT 1) AS tblLastName,
(SELECT BirthDate FROM patient WHERE ID > 26360 LIMIT 1) AS tblBirthDate,
(SELECT Location FROM patient WHERE ID > 68356 AND Location != '' LIMIT 1) AS tblLocation

Now in the ID > 26360 from the above query 26360 is that random number and > is used to avoid the possibility if 26360 was deleted

PROBLEM:

if any of the sub query returns no result complete query fails and return nothing.

Answer 1

Try this:

SELECT (SELECT FirstName FROM patient WHERE ID > 11445 AND FirstName != '' LIMIT 1) AS tblFirstName,
         (SELECT LastName FROM patient WHERE ID > 74964 AND LastName != '' LIMIT 1) AS tblLastName,
         (SELECT BirthDate FROM patient WHERE ID > 26360 LIMIT 1) AS tblBirthDate,
         (SELECT Location FROM patient WHERE ID > 68356 AND Location != '' LIMIT 1) AS tblLocation