3.10.8 mysqli_result::fetch_fields, mysqli_fetch

3.10.8 `mysqli_result::fetch_fields`, `mysqli_fetch_fields`

mysqli_result::fetch_fields
mysqli_fetch_fields
Returns an array of objects representing the fields in a result set

Description

Object oriented style

public array mysqli_result::fetch_fields();

Procedural style

array mysqli_fetch_fields(mysqli_result result);

This function serves an identical purpose to the mysqli_fetch_field function with the single difference that, instead of returning one object at a time for each field, the columns are returned as an array of objects.

Parameters

result: Procedural style only: A result set identifier returned by mysqli_query, mysqli_store_result or mysqli_use_result.

Return Values

Returns an array of objects which contains field definition information or false if no field information is available.

Table 3.18 Object properties

Property	Description
name	The name of the column
orgname	Original column name if an alias was specified
table	The name of the table this field belongs to (if not calculated)
orgtable	Original table name if an alias was specified
max_length	The maximum width of the field for the result set.
length	The width of the field, in bytes, as specified in the table definition. Note that this number (bytes) might differ from your table definition value (characters), depending on the character set you use. For example, the character set utf8 has 3 bytes per character, so varchar(10) will return a length of 30 for utf8 (103), but return 10 for latin1 (101).
charsetnr	The character set number (id) for the field.
flags	An integer representing the bit-flags for the field.
type	The data type used for this field
decimals	The number of decimals used (for integer fields)

Examples

Example 3.118 Object oriented style

<?php
$mysqli = new mysqli("127.0.0.1", "root", "foofoo", "sakila");

/* check connection */
if ($mysqli->connect_errno) {
    printf("Connect failed: %s\n", $mysqli->connect_error);
    exit();
}

foreach (array('latin1', 'utf8') as $charset) {

    // Set character set, to show its impact on some values (e.g., length in bytes)
    $mysqli->set_charset($charset);

    $query = "SELECT actor_id, last_name from actor ORDER BY actor_id";

    echo "======================\n";
    echo "Character Set: $charset\n";
    echo "======================\n";
    
    if ($result = $mysqli->query($query)) {

        /* Get field information for all columns */
        $finfo = $result->fetch_fields();

        foreach ($finfo as $val) {
            printf("Name:      %s\n",   $val->name);
            printf("Table:     %s\n",   $val->table);
            printf("Max. Len:  %d\n",   $val->max_length);
            printf("Length:    %d\n",   $val->length);
            printf("charsetnr: %d\n",   $val->charsetnr);
            printf("Flags:     %d\n",   $val->flags);
            printf("Type:      %d\n\n", $val->type);
        }
        $result->free();
    }
}
$mysqli->close();
?>

Example 3.119 Procedural style

<?php
$link = mysqli_connect("127.0.0.1", "my_user", "my_password", "sakila");

/* check connection */
if (mysqli_connect_errno()) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
}

foreach (array('latin1', 'utf8') as $charset) {

    // Set character set, to show its impact on some values (e.g., length in bytes)
    mysqli_set_charset($link, $charset);

    $query = "SELECT actor_id, last_name from actor ORDER BY actor_id";

    echo "======================\n";
    echo "Character Set: $charset\n";
    echo "======================\n";

    if ($result = mysqli_query($link, $query)) {

        /* Get field information for all columns */
        $finfo = mysqli_fetch_fields($result);

        foreach ($finfo as $val) {
            printf("Name:      %s\n",   $val->name);
            printf("Table:     %s\n",   $val->table);
            printf("Max. Len:  %d\n",   $val->max_length);
            printf("Length:    %d\n",   $val->length);
            printf("charsetnr: %d\n",   $val->charsetnr);
            printf("Flags:     %d\n",   $val->flags);
            printf("Type:      %d\n\n", $val->type);
        }
        mysqli_free_result($result);
    }
}

mysqli_close($link);
?>

The above examples will output:

======================
Character Set: latin1
======================
Name:      actor_id
Table:     actor
Max. Len:  3
Length:    5
charsetnr: 63
Flags:     49699
Type:      2

Name:      last_name
Table:     actor
Max. Len:  12
Length:    45
charsetnr: 8
Flags:     20489
Type:      253

======================
Character Set: utf8
======================
Name:      actor_id
Table:     actor
Max. Len:  3
Length:    5
charsetnr: 63
Flags:     49699
Type:      2

Name:      last_name
Table:     actor
Max. Len:  12
Length:    135
charsetnr: 33
Flags:     20489