MySQL Query to receive random combinations from two tables

Alright, here is my issue, I have two tables, one named firstnames and the other named lastnames. What I am trying to do here is to find 100 of the possible combinations from these names for test data. The firstnames table has 5494 entries in a single column, and the lastnames table has 88799 entries in a single column. Th开发者_JS百科e only query that I have been able to come up with that has some results is:

select * from (select * from firstnames order by rand()) f LEFT JOIN (select * from lastnames order by rand()) l on 1=1 limit 10;

The problem with this code is that it selects 1 firstname and gives every lastname that could go with it. While this is plausible, I will have to set the limit to 500000000 in order to get all the combinations possible without having only 20 first names(and I'd rather not kill my server). However, I only need 100 random generations of entries for test data, and I will not be able to get that with this code. Can anyone please give me any advice?

Is this what you're looking for?

SELECT * 
FROM (

SELECT firstname
FROM firstnames
ORDER BY RAND( ) 
LIMIT 10
) AS tb1
JOIN (

SELECT lastname
FROM lastnames
ORDER BY RAND( ) 
LIMIT 10
) AS tb2 ON 1=1

This will give you all combinations of 10 random first names and 10 random last names. Change the limits to change how many names you want to combine.

Order de final result by rand() as well before you do limit 10, that should shuffle your 500000000 results around to give you what you want.