(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)
pg_update — Update table
$connection,$table_name,$values,$conditions,$flags = PGSQL_DML_EXEC
pg_update() updates records that matches
conditions with values.
If flags is specified,
pg_convert() is applied to
values with the specified flags.
By default pg_update() passes raw values.
Values must be escaped or the PGSQL_DML_ESCAPE flag
must be specified in flags.
PGSQL_DML_ESCAPE quotes and escapes parameters/identifiers.
Therefore, table/column names become case sensitive.
Note that neither escape nor prepared query can protect LIKE query, JSON, Array, Regex, etc. These parameters should be handled according to their contexts. i.e. Escape/validate values.
connectionAn PgSql\Connection instance.
table_nameName of the table into which to update rows.
values
An array whose keys are field names in the table table_name,
and whose values are what matched rows are to be updated to.
conditions
An array whose keys are field names in the table table_name,
and whose values are the conditions that a row must meet to be updated.
flags
Any number of PGSQL_CONV_FORCE_NULL ,
PGSQL_DML_NO_CONV ,
PGSQL_DML_ESCAPE ,
PGSQL_DML_EXEC ,
PGSQL_DML_ASYNC or
PGSQL_DML_STRING combined. If PGSQL_DML_STRING is part of the
flags then query string is returned. When PGSQL_DML_NO_CONV
or PGSQL_DML_ESCAPE is set, it does not call pg_convert() internally.
Returns true on success or false on failure. Returns string if PGSQL_DML_STRING is passed
via flags.
| Version | Description |
|---|---|
| 8.1.0 |
The connection parameter expects an PgSql\Connection
instance now; previously, a resource was expected.
|
Example #1 pg_update() example
<?php
$db = pg_connect('dbname=foo');
$data = array('field1'=>'AA', 'field2'=>'BB');
// This is safe somewhat, since all values are escaped.
// However PostgreSQL supports JSON/Array. These are not
// safe by neither escape nor prepared query.
$res = pg_update($db, 'post_log', $_POST, $data);
if ($res) {
echo "Data is updated: $res\n";
} else {
echo "User must have sent wrong inputs\n";
}
?>Using pg_update() and pg_insert() without key validation is not secure!
You need to check which data pairs you get, and if you want to allow to updated this column.
Example:
You have a table with tree colums: username, password, userlevel.
Your users may change only their username, and their password but not their userlevel.
If you don't filter the keys in the request array, every user can now change his userlevel just by sending a POST Request with "userlevel=>100".
So if you don't check if the key are allowed in your request array you'll get serious sql injection vulnarabilities in your code.> Return Values
>
> Returns TRUE on success or FALSE on failure. Returns string if
> PGSQL_DML_STRING is passed via options.
I have found in my copy of PHP (version 4.4.0) that if you use the 'PGSQL_DML_STRING' option, the function does not execute any query. It merely returns the query which would have been executed.
Another thing I noticed, pg_update does not seem to make use of pg_trace (atleast in 4.4.0).
PS this isn't a bug report, just an explanation of some undocumented features I noticed. As the manual says, the function is still in development so this behaviour may differ from version to version.This function is similar to PEAR::DB's autoExecute() function, with the only difference being that the where clause is an array instead of a string.
Also, if you want to use your instance of the DB class with this function, you can reference the existing resource connection with $db->connection.
An example would be:
<?
pg_update($db->connection, $arr_update, $arr_where);
?>