I'm using PHP ADOdb and I can get the result set:
$result = &$db->Execute($query);
How do I get the field names from that one row and loop through it?
(I'm using access database if that matters.)
It will depend on your fetch mode - if you setFetchMode to ADODB_FETCH_NUM (probably the default) each row contains a flat array of columns. If you setFetchMode to ADODB_FETCH_ASSOC you get an associative array where you can access each value by a key. The following is taken from ADODB documentation - http://phplens.com/lens/adodb/docs-adodb.htm#ex1
$db->SetFetchMode(ADODB_FETCH_NUM);
$rs1 = $db->Execute('select * from table');
$db->SetFetchMode(ADODB_FETCH_ASSOC);
$rs2 = $db->Execute('select * from table');
print_r($rs1->fields); # shows array([0]=>'v0',[1] =>'v1')
print_r($rs2->fields); # shows array(['col1']=>'v0',['col2'] =>'v1')
To loop through a set of results:
$result = &$db->Execute($query);
foreach ($result as $row) {
print_r($row);
}
Small improvement to the solution posted by @thetaiko.
If you are ONLY needing the field names, append LIMIT 1 to the end of your select statement (as shown below). This will tell the server to send you a single row with column names, rather than sending you the entire table.
SELECT * FROM table LIMIT 1;
I'm working with a table that contains 9.1M records, so this minor change speeds up the query significantly!
This is a function I use to return a field array - I've stripped out some extra stuff that, for example, allows it to work with other DBs than MySQL.
function getFieldNames($strTable, $cn) {
$aRet = array();
# Get Field Names:
$lngCountFields = 0;
$strSQL = "SELECT * FROM $strTable LIMIT 1;";
$rs = $cn->Execute($strSQL)
or die("Error in query:
$strSQL
" . $cn->ErrorMsg());
if (!$rs->EOF) {
for ($i = 0; $i < $rs->FieldCount(); $i++) {
$fld = $rs->FetchField($i);
$aRet[$lngCountFields] = $fld->name;
$lngCountFields++;
}
}
$rs->Close();
$rs = null;
return $aRet;
}
Edit: just to point out that, as I say, I've stripped out some extra stuff, and the EOF check is therefore no longer necessary in the above, reduced version.
I initally tried to use MetaColumnNames, but it gave differing results in VisualPHPUnit and actual site, while running from the same server, so eventually I ended up doing something like this:
$sql = "select column_name, column_key, column_default, data_type, table_name, table_schema from information_schema.columns";
$sql .= ' where table_name="'.$table.'" and table_schema="'.$database_name.'"';
$result = $conn->Execute($sql);
while($row = $result->fetchRow()) {
$out[] = strToUpper($row['column_name']);
}
I think it should work with mysql, mssql and postgres. The benefit of doing it like this, is that you can get the column names, even if a query from a table returns an empty set.
If you need the Coloumn names even for empty tables or for joins about multiple tables use this:
$db->Execute("SELECT .......");
// FieldTypesArray - Reads ColoumnInfo from Result, even for Joins
$colInfo = $res->FieldTypesArray();
$colNames = array();
foreach($colNames as $info) $colInfo[] = $info->name;