mssql_fetch_field
(PHP 4, PHP 5, PECL odbtp >= 1.1.1)
mssql_fetch_field — Get field information
Description
$result
[, int $field_offset
= -1
] )mssql_fetch_field() can be used in order to obtain information about fields in a certain query result.
Parameters
-
result
-
The result resource that is being evaluated. This result comes from a call to mssql_query().
-
field_offset
-
The numerical field offset. If the field offset is not specified, the next field that was not yet retrieved by this function is retrieved. The
field_offset
starts at 0.
Return Values
Returns an object containing field information.
The properties of the object are:
- name - column name. if the column is a result of a function, this property is set to computed#N, where #N is a serial number.
- column_source - the table from which the column was taken
- max_length - maximum length of the column
- numeric - 1 if the column is numeric
- type - the column type.
Examples
Example #1 mssql_fetch_field() example
<?php
// Connect to MSSQL and select the database
mssql_connect('MANGO\SQLEXPRESS', 'sa', 'phpfi');
mssql_select_db('php');
// Send a select query to MSSQL
$query = mssql_query('SELECT * FROM [php].[dbo].[persons]');
// Construct table
echo '<h3>Table structure for \'persons\'</h3>';
echo '<table border="1">';
// Table header
echo '<thead>';
echo '<tr>';
echo '<td>Field name</td>';
echo '<td>Data type</td>';
echo '<td>Max length</td>';
echo '</tr>';
echo '</thead>';
// Dump all fields
echo '<tbody>';
for ($i = 0; $i < mssql_num_fields($query); ++$i) {
// Fetch the field information
$field = mssql_fetch_field($query, $i);
// Print the row
echo '<tr>';
echo '<td>' . $field->name . '</td>';
echo '<td>' . strtoupper($field->type) . '</td>';
echo '<td>' . $field->max_length . '</td>';
echo '</tr>';
}
echo '</tbody>';
echo '</table>';
// Free the query result
mssql_free_result($query);
?>
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Расширения для работы с базами данных
- Расширения для работы с базами данных отдельных производителей
- Microsoft SQL Server
- mssql_bind
- mssql_close
- mssql_connect
- mssql_data_seek
- mssql_execute
- mssql_fetch_array
- mssql_fetch_assoc
- mssql_fetch_batch
- mssql_fetch_field
- mssql_fetch_object
- mssql_fetch_row
- mssql_field_length
- mssql_field_name
- mssql_field_seek
- mssql_field_type
- mssql_free_result
- mssql_free_statement
- mssql_get_last_message
- mssql_guid_string
- mssql_init
- mssql_min_error_severity
- mssql_min_message_severity
- mssql_next_result
- mssql_num_fields
- mssql_num_rows
- mssql_pconnect
- mssql_query
- mssql_result
- mssql_rows_affected
- mssql_select_db
Коментарии
Using this function with MSSQL 7, $returned->column_source is the column name, not the table name as it should be.
It seems fairly hard to get a list of the tables from your database using MSSQL but this seems to do the trick. This is set to get only the User Tables and ignores the sytem tables.
<?php
mssql_connect("server","","") or die ("help me!");
mssql_select_db("") or die ("Noooo!");
$result = mssql_query ("sp_tables");
$fields = mssql_num_fields ($result);
$rows = mssql_num_rows ($result);
for ($f=0; $f<$rows; $f++) {
$CHKTYPE=GetField($result,"TABLE_TYPE",$f);
if($CHKTYPE=='TABLE'){
//$name = mssql_fetch_field($result, 2);
$field=GetField($result,"TABLE_NAME",$f)."<br>";
echo $field;
}
}
?>
When you mssql_fetch_field(int result), you need to do loop to get the name of each field. Something like:
while($fld = mssql_fetch_field($rs)){
echo $fld->name . "<br>";
}
I am wondering why we cannot refer it by a field number.
As kubalaa at bigfoot dot com note mssql_fetch_field->column_source return field name instead table name also with MSSQL2000 connection. Be adwised!!!
Be aware that this function will only return the first 30 characters of the name of the column. If the actual column name is longer, it will be truncated. This is at least true with the following setup:
PHP 4.3.1
MSSQL 8.00.760
Have a good day everyone!
Brian
If you want to describe table structure (like mysql 'desc table' command), sending this query might help:
<?
$sql = "SELECT c.name, c.isnullable, c.length, c.colstat, t.name type
FROM syscolumns c, systypes t, sysobjects o
WHERE o.name = '$table' AND o.id = c.id AND c.xtype = t.xtype";
?>
I suspect the colstat field in syscolumns table indicates primary key when its value is 1
commenting Reynard Hilman:
for me it looks like the colstat field value of 1 in syscolumns table indicates an Identity Column.
For really detailed table information, use syscolumns, like this:
SELECT c.name, c.prec, c.scale, t.name type
FROM syscolumns c, systypes t, sysobjects o
WHERE o.name = 'yourtablename' AND o.id = c.id AND c.xtype = t.xtype
For other properties see the MS SQL online help. Search for 'syscolumns'.
Or an another solution:
sp_columns @table_name = 'yourtablename', @column_name = 'thecolumnname'
//no "select ..." !!!!
This gives info about only the specified column.
If you want to describe table like DESCRIBE in MySQL you can use this:
$sql = <<<SQL
SELECT column_name,data_type,column_default,is_nullable
FROM
information_schema.tables AS t
JOIN
information_schema.columns AS c ON
t.table_catalog=c.table_catalog AND
t.table_schema=c.table_schema AND
t.table_name=c.table_name
WHERE
t.table_name='TABLE-NAME'
SQL;
kubalaa at bigfoot dot com first reported the problem that column_source contains the FIELD name instead of the source TABLE name 04-Apr-2000 03:58. The bug has been reported as well.
For those who wonder if it was fixed over the past 8 years: No, the bug still is the same, no workaround available.