Question

Can someone help me rowCount() when I have values and empty values in mysql

for example:

id        column1          column2           idcolumn
1           2                                   1  
2           3                                   1
3           1                                   1
4           0                                   1


$CountQuery = "SELECT column1 FROM follow WHERE idcolumn= ?";
$Count = $dbh->prepare($CountQuery);
$Count -> execute(array($idcolumn)); //where $idcolumn = 1
$num_1 = $Count->rowCount();
echo $num_1;

this should give me a count of 4, but I’m trying to distinguish between column1 and column2, so I can find counts where if I wanted to create a query with $num_2, it should give me a count of 0.

Answer 1

Use COUNT(column) to count the number of rows with non-NULL values in that column.

$CountQuery = "SELECT COUNT(column1) AS `count1`, COUNT(column2) AS `count2` FROM follow WHERE idcolumn = ?";
$Count = $dbh->prepare($CountQuery);
$Count->execute(array($idcolumn)); //where $idcolumn = 1
$row = $Count->fetch(PDO::FETCH_ASSOC);

$num_1 = $row['count1'];
$num_2 = $row['count2'];