dougouqin0763 2013-03-30 21:23
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在做了一个while循环之后,检查是否有任何行,如果没有,则回显一些PDO

I have a while loop that fetches rows from the MySQL database.

But I want to check if there are rows at all, if the table is empty, then echo an error.

I have a dirty way of doing this:

while($row = $fetch->fetch( PDO::FETCH_ASSOC ) $random[] = $row['a_column'] ) {
    if (count($random) == 0) {
    echo ' It's empty... ';
    } else {
echo $row['a_column'];
}

Problem is that I have many columns and I am sure this is an extremely dirty way of doing so..

Problem

I am using PDO and I am not really sure how would I check if there are any rows in the table..

Question

How would I find out that the table doesn't contains any rows, if it doesn't, echo error.. if it does, echo results of a_column?.

Thanks!

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  • dook0034 2013-03-30 21:26
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    You can use $fetch->columnCount(). If there are no results it will return 0. It also might be possible to use $fetch->rowCount(), although the manual doesn't recommend it for SELECT statements.

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