03-14-2011
question about popen in C
does popen print out the executed string result in stdout, or just evaluate it and not print the result?
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LEARN ABOUT PHP
pdostatement.fetchcolumn
PDOSTATEMENT.FETCHCOLUMN(3) 1 PDOSTATEMENT.FETCHCOLUMN(3)
PDOStatement::fetchColumn - Returns a single column from the next row of a result set
SYNOPSIS
public mixed PDOStatement::fetchColumn ([int $column_number])
DESCRIPTION
Returns a single column from the next row of a result set or FALSE if there are no more rows.
Note
PDOStatement.fetchColumn(3) should not be used to retrieve boolean columns, as it is impossible to distinguish a value of FALSE from
there being no more rows to retrieve. Use PDOStatement.fetch(3) instead.
PARAMETERS
o $column_number
- 0-indexed number of the column you wish to retrieve from the row. If no value is supplied, PDOStatement.fetchColumn(3) fetches
the first column.
RETURN VALUES
PDOStatement.fetchColumn(3) returns a single column in the next row of a result set.
Warning
There is no way to return another column from the same row if you use PDOStatement.fetchColumn(3) to retrieve data.
EXAMPLES
Example #1
Return first column of the next row
<?php
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();
print("Fetch the first column from the first row in the result set:
");
$result = $sth->fetchColumn();
print("name = $result
");
print("Fetch the second column from the second row in the result set:
");
$result = $sth->fetchColumn(1);
print("colour = $result
");
?>
The above example will output:
Fetch the first column from the first row in the result set:
name = lemon
Fetch the second column from the second row in the result set:
colour = red
SEE ALSO
PDO.query(3), PDOStatement.fetch(3), PDOStatement.fetchAll(3), PDO.prepare(3), PDOStatement.setFetchMode(3).
PHP Documentation Group PDOSTATEMENT.FETCHCOLUMN(3)