mysql_field_len

mysql_fetch_row

[edit] Last updated: Fri, 18 May 2012

mysql_field_flags

(PHP 4, PHP 5)

mysql_field_flags — Liefert die Flags des spezifizierten Feldes in einem Anfrageergebnis

Beschreibung

string mysql_field_flags ( resource $result , int $field_offset )

mysql_field_flags() liefert die Flags des Feldes mit dem übergebenen Offset. Die Flags werden als einzelne Worte pro Flag und durch ein einziges Leerzeichen getrennt geliefert, so dass sie leicht mit explode() getrennt werden können.

Parameter-Liste

Ergebnis: Das Ergebnis Ressource, das ausgewertet wird. Dieses Ergebnis kommt von einem Aufruf von mysql_query().
Feldoffset: Der numerische Offset des Feldes. Der Feldoffset beginnt bei 0. Falls Feldoffset nicht existiert, wird eine Warnung der Stufe E_WARNING erzeugt.

Rückgabewerte

Gibt eine Zeichenkette aus Flags, die mit dem ERgebnis assoziiert sind, zurück Im Fehlerfall wird FALSE zurückgegeben..

Die folgenden Flags werden geliefert, wenn Ihre Version von MySQL aktuell genug ist, diese zu unterstützen: "not_null", "primary_key", "unique_key", "multiple_key", "blob", "unsigned", "zerofill", "binary", "enum", "auto_increment" und "timestamp".

Beispiele

Beispiel #1 Ein mysql_field_flags() Beispiel


<?php
$result = mysql_query("SELECT id,email FROM people WHERE id = '42'");
if (!$result) {
    echo 'Konnte Abfrage nicht ausführen: ' . mysql_error();
    exit;
}
$flags = mysql_field_flags($result, 0);

echo $flags;
print_r(explode(' ', $flags));
?>

Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:

not_null primary_key auto_increment
Array
(
    [0] => not_null
    [1] => primary_key
    [2] => auto_increment
)

Anmerkungen

Hinweis:
Für die Abwärtskompatibiliät kann der folgende veraltete Alias verwendet werden: mysql_fieldflags()

Siehe auch

mysql_field_type() - Liefert den Typ des spezifizierten Feldes in einem Ergebnis
mysql_field_len() - Liefert die Länge des angegebenen Feldes

mysql_field_len

mysql_fetch_row

[edit] Last updated: Fri, 18 May 2012

add a note User Contributed Notes mysql_field_flags

play at arcadevillage dot com 03-Aug-2009 07:07


To really backup the database values, I made a little changement :





My code really looks like bomas 's code, but there is an important diffence :





<?php


$nbc = mysql_num_fields($req_table);


while ($ligne = mysql_fetch_array($req_table))


  {


    $insertions = "INSERT INTO $table VALUES(";


     for ($i=0; $i<$nbc; $i++)


        {


          if ( $i > 0 ) $insertions .= ", ";


          if ( !isset($ligne[$i])) 


            $insertions .= "NULL";


          else


            $insertions .= "'" . mysql_real_escape_string($ligne[$i]). "'";


        }


     $insertions .= ");";


     $dumpsql[] = $insertions;


   }


?>





$dumpslq is the variable where I put the insertion orders before writting them in a text file.





Before, I test that the values if not NULL into the field because it is the only way to make the difference, for example for string text fields, between NULL values and empty strings.





If you don't make this test, you should find empty string instead of NULL values when you do the backup.

Bob 05-May-2009 03:00


To parse an enum/set type correctly, including strings like ENUM('a\'b','c'), here is an almost pcre-free way that works well.

<?php

function parse_enum_values($typestr)

{

    // remove ENUM/SET part

    $typestr = preg_replace('/^(enum|set)/i', '', $typestr);

    // trim '(', ')', ' off the ends of the string and then explode it on ','

    return trim(explode("','", $typestr), "(')");

}

?>

It works because explode is looking for ',' - not ',\'.

dev at rgbworld dot com 13-Apr-2008 03:45


With regard to get_fields() by pike-php at kw dot nl



For 'enum and 'set' the code improperly parses single quote marks that should be allowed in the elements.



For example EMUM('a\'s', 'b') is parsed into 3 array elements when it should be 2.



Wrong:

[args] => Array

(

[0] => a

[1] => s

[2] => b

)



It should give:

[args] => Array

(

[0] => a's

[1] => b

)



I am not good with preg, but if someone could provide a solution, that would be great. Thank you!

bomas at cities-of-faith dot com 08-Sep-2005 01:52


well, to make a complete backup of your database, i suggest this code:



//open database here

$tab_status = mysql_query("SHOW TABLE STATUS");

while($all = mysql_fetch_assoc($tab_status)):

    $tbl_stat[$all[Name]] = $all[Auto_increment];

endwhile;

unset($backup);

$tables = mysql_list_tables('cofadmin');

while($tabs = mysql_fetch_row($tables)):

    $backup .= "--\n--Tabel structuur voor `$tabs[0]`\n--\n\nDROP IF EXISTS TABLE `$tabs[0]`\nCREATE TABLE IF NOT EXISTS `$tabs[0]` (&nbsp;";

    $res = mysql_query("SHOW CREATE TABLE $tabs[0]");

    while($all = mysql_fetch_assoc($res)):

        $str = str_replace("CREATE TABLE `$tabs[0]` (", "", $all['Create Table']);

        $str = str_replace(",", ",&nbsp;", $str);

        $str2 = str_replace("`) ) TYPE=MyISAM ", "`)\n ) TYPE=MyISAM ", $str);

        $backup .= $str2." AUTO_INCREMENT=".$tbl_stat[$tabs[0]].";\n\n";

    endwhile;

    $backup .= "--\n--Gegevens worden uitgevoerd voor tabel `$tabs[0]`\n--\n\n";

    $data = mysql_query("SELECT * FROM $tabs[0]");

    while($dt = mysql_fetch_row($data)):

        $backup .= "INSERT INTO `$tabs[0]` VALUES('$dt[0]'";

        for($i=1; $i<sizeof($dt); $i++):

            $backup .= ", '$dt[$i]'";

        endfor;

        $backup .= ");\n";

    endwhile;

    $backup .= "\n-- --------------------------------------------------------\n\n";

endwhile;

echo $backup;



this displayes your data the same way as phpmyadmin does.



hope it helps some of you guys

Greetz

pike-php at kw dot nl 14-Jul-2005 04:55


ok, sorry for the code bloat :) but this is how I 

get the full power of mysql's DESCRIBE table statement, in 

an associative array, including defaults, enum values, float radix et all.



it assumes mysql returns the type as 

   "type[(arg[,arg..])] [ add]"

like

   "float(20,6) unsigned"

   "enum('yes','no')"

etc



<?



function getFields($tablename) {

    

        $fields = array();

        $fullmatch         = "/^([^(]+)(\([^)]+\))?(\s(.+))?$/";

        $charlistmatch     = "/,?'([^']*)'/";

        $numlistmatch     = "/,?(\d+)/";

        

        $fieldsquery .= "DESCRIBE $tablename";

        $result_fieldsquery = mysql_query($fieldsquery) or die(mysql_error());

        while ($row_fieldsquery = mysql_fetch_assoc($result_fieldsquery)) {

            

            $name     = $row_fieldsquery['Field'];

            $fields[$name] = array();

            $fields[$name]["type"]         = "";

            $fields[$name]["args"]         = array();

            $fields[$name]["add"]          = "";

            $fields[$name]["null"]        = $row_fieldsquery['Null'];

            $fields[$name]["key"]        = $row_fieldsquery['Key'];

            $fields[$name]["default"]    = $row_fieldsquery['Default'];

            $fields[$name]["extra"]        = $row_fieldsquery['Extra'];

            

            $fulltype     = $row_fieldsquery['Type'];

            $typeregs = array();

            

            if (preg_match($fullmatch, $fulltype, $typeregs)) {

                $fields[$name]["type"] = $typeregs[1];

                if ($typeregs[4]) $fields[$name]["add"] = $typeregs[4];

                $fullargs = $typeregs[2];

                $argsreg = array();

                if (preg_match_all($charlistmatch, $fullargs, $argsreg)) {

                    $fields[$name]["args"] = $argsreg[1];

                } else {

                    $argsreg = array();

                    if (preg_match_all($numlistmatch, $fullargs, $argsreg)) {

                        $fields[$name]["args"] = $argsreg[1];

                    } else die("cant parse type args: $fullargs");

                }

            } else die("cant parse type: $fulltype");



        }

        return $fields;

            

    }



?>

buttrose at unimelb dot edu dot au 20-Oct-2004 07:26


This function is essential for writing a generic table editor (ie one that just takes the name of the table and works out what fields it has, types, sizes etc.). Unfortunately, I am using psotgreSQL not mySql. Postgres has field_type and field_size functions  but not as far as I can tell an equivalent of the mysql_field_flags() function. Without it, there is no way I can do generic ADDs and INSERTs. 



Anyone know a workaround to get this information (eg is the field a primary key? Can it be NULL? Is it auto_increment?) in Postgres?



Cheers



Rob Buttrose

amir at scrounch dot com 17-Aug-2003 10:39


returns primary keys of a table using 'show keys'


although it is possible to use desc, show keys offers possible enhancements such a getting sequence in index along with it





function getPrimaryKeyOf($table, $link) {


  $pk = Array(); 





  $sql = 'SHOW KEYS FROM `'.$table.'`'; 


  $res = mysql_query($table, $link) or die(mysql_error()); 


  while ($row = mysql_fetch_assoc($res)) { 


    if ($row['Key_name']=='PRIMARY') 


      array_push($pk, $row['Column_name']); 


  } 


  return $pk; 


}

simone dot t at betisgroup dot com 10-Apr-2003 04:20


Another examples :



####################################



function field_keys($host, $user, $password, $database, $field ) {

   $db_link = mysql_connect($host, $user, $password) or die ("error connect");

   mysql_select_db($database,$db_link);

   $query="DESC $field";

   $results=mysql_query($query);

   $i=0;

   while ($row=mysql_fetch_array($results)) {

         if ($row[Key]=="PRI") {

            $array_keys[$i]=$row[Field];

         }

         $i++;

  }

   return $array_keys;

}



####################################



//Example of Main...

$tmp = field_keys("localhost", "myuser", "mypassword", "mydb", "field_name" );



// ...loop through array...

foreach ( $tmp as $array_tmp){

    print "<br>";

    print $array_tmp;

    print "<br>";

}

justin DOT flavin AT ntlworld DOT com 06-Dec-2002 10:36


Sometimes, when writing a generic function or class, you want your script to be able to determine what the primary key of a table is. 

/* usual MySQL stuff */

$query="DESC UsersTable";

$results=mysql_query($query);



while ($row=mysql_fetch_array($results))

{

if ($row[Type]="PRI")

    {

print "I found the primary key! <br>";

$UserKey=$row[Field];

print $row[Field];

/* drop out , as we've found the key */    

exit;

    }

}



..... later on we might have something like



< some sort of loop through records >



print "<a href='View_User_record.php?userkey=$UserKey'> Users Name </a>";



<end loop>



What's also interesting is the useful data you can get from

a DESC query.



The following prints out the array values grabbed by mysql_fetch_array on a DESC query - VERY useful stuff!!!



/* usual MySQL stuff */

$query="DESC UsersTable";

$results=mysql_query($query);



while ($row=mysql_fetch_array($results))

{

print "<pre>";

print_r ($row);

print "</pre>";

}

jakemsr at jakemsr dot com 31-Oct-2002 12:32


I didn't find anything to get the valid values for

ENUM or SET column types, so I came up with the

following



function mysql_enum_values($table, $field)

{

    $sql = "SHOW COLUMNS FROM $table LIKE '$field'";

    $sql_res = mysql_query($sql)

        or die("Could not query:\n$sql");

    $row = mysql_fetch_assoc($sql_res);

    mysql_free_result($sql_res);

    return(explode("','",

        preg_replace("/.*\('(.*)'\)/", "\\1",

            $row["Type"])));

}

cufarley at nirvanet dot net 11-Jul-2001 05:36


Using the "DESC TableName" command may also do the trick and is a bit shorter.

jurgen at alienguitar dot com 10-Jun-2001 04:50


The previous problem to get the default values of a column:


Use the following query and parse the 'Default' column:





"SHOW COLUMNS FROM TableName"





or for a single entry:





"SHOW COLUMNS FROM TableName LIKE 'column'"





It will give you also values for Type,  Null, Key and Extra (check with mysql program first, so you see what you get ;-)

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