SQL，检查表中所有记录的值是否大于5 [关闭]

Question

I am using PHP and I need a sql query which will check whether all records value greater then 5.. Won't return any data from database. Just will return true if all records are greater then 5.

If the answer is true I will update another table..

Pseudo Code is

if(the value column in table1 is greater then 5 for all records)
then
    $update = mysql_query("UPDATE table2 SET q_value = '0' ")
else
do nothing


Table Example:
------------------------

| question |  value   |
|    X1    |     6    |
|    X2    |     6    |
|    X3    |     6    | //value column for all records are greater then 5 
|    X4    |     7    | //must return true
|    X5    |     8    | //and will update table2
|    X6    |     6    |

| question |  value   |
|    X1    |     6    |
|    X2    |     3    |
|    X3    |     0    | //value column for all records not greater then 5 
|    X4    |     7    | //there are 0 and 3 values and must return false
|    X5    |     8    | //won't update table2 
|    X6    |     6    |

Could you please give me an idea for this. How can I check something for all records. Won't return any data. Just will return true if all values greater then something...

Thank you in advance

Answer 1

select count(*)
from table1
where value <= 5

If 0 is returned, it's TRUE, FALSE otherwise.