MySQL Funkcje
i found a pretty nice way, this db class/function will accept an array of arrays of querys, it will auto check every line for affected rows in db, if one is 0 it will rollback and return false, else it will commit and return true, the call to the function is simple and is easy to read etc
----------
<?php
class MySQLDB
{
private $connection; // The MySQL database connection
/* Class constructor */
function MySQLDB(){
/* Make connection to database */
$this->connection = mysql_connect(DB_SERVER, DB_USER, DB_PASS) or die(mysql_error());
mysql_select_db(DB_NAME, $this->connection) or die(mysql_error());
}
/* Transactions functions */
function begin(){
$null = mysql_query("START TRANSACTION", $this->connection);
return mysql_query("BEGIN", $this->connection);
}
function commit(){
return mysql_query("COMMIT", $this->connection);
}
function rollback(){
return mysql_query("ROLLBACK", $this->connection);
}
function transaction($q_array){
$retval = 1;
$this->begin();
foreach($q_array as $qa){
$result = mysql_query($qa['query'], $this->connection);
if(mysql_affected_rows() == 0){ $retval = 0; }
}
if($retval == 0){
$this->rollback();
return false;
}else{
$this->commit();
return true;
}
}
};
/* Create database connection object */
$database = new MySQLDB;
// then from anywhere else simply put the transaction queries in an array or arrays like this:
function function(){
global $database;
$q = array (
array("query" => "UPDATE table WHERE something = 'something'"),
array("query" => "UPDATE table WHERE something_else = 'something_else'"),
array("query" => "DELETE FROM table WHERE something_else2 = 'something_else2'"),
);
$database->transaction($q);
}
?>
mysql_affected_rows
(PHP 4, PHP 5)
mysql_affected_rows — Zwraca liczbę wierszy przetworzonych w poprzedniej operacji MySQL
Opis
int mysql_affected_rows
([ resource
$identyfikator_połączenia
] )
Pobiera liczbę wierszy przetworzonych w ostatnim zapytaniu INSERT, UPDATE, REPLACE
lub DELETE skojarzonym z identyfikator_połączenia.
Parametry
-
identyfikator_połączenia -
Połączenie MySQL. Jeśli identyfikator połączenia nie zostanie podany, użyte zostanie ostatnie połączenie otwarte przez mysql_connect(). Jeśli połączenie takie nie zostanie znalezione, funkcja spróbuje nawiązać połączenie tak, jakby wywołana została funkcja mysql_connect() bez argumentów. Jeśli żadne połączenie nie zostanie znalezione lub nawiązane, wygenerowany zostanie błąd poziomu
E_WARNING.
Zwracane wartości
Zwraca liczbę przetworzonych wierszy w przypadku sukcesu i -1 jeśli ostatnie zapytanie zawiedzie.
Jeżeli ostatnim zapytaniem było DELETE bez użycia klauzuli WHERE, wszystkie rekordy zostaną usunięte z tabeli, ale funkcja zwróci zero w wersjach MySQL starszych niż 4.1.2.
Podczas operacji UPDATE, MySQL nie aktualizuje kolumn w których nowa wartość jest identyczna z poprzednią. Możliwe jest zatem, że zwrócona przez mysql_affected_rows() liczba nie będzie odpowiadać liczbie wierszy pasujących do zapytania, ale tych, które zostały faktycznie zmienione.
Wyrażenie REPLACE najpierw skasuje rekord z tym samym kluczem głównym następnie wstawi nowy rekord. Ta funkcja zwraca liczbę skasowanych rekordów plus liczbę wstawionych rekordów.
Przykłady
Przykład #1 Przykład mysql_affected_rows()
<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
die('Nie można się połączyć: ' . mysql_error());
}
mysql_select_db('mydb');
/* to powinno zwrócić prawidłową liczbę usuniętych rekordów */
mysql_query('DELETE FROM mytable WHERE id < 10');
printf("Usuniętych rekordów: %d\n", mysql_affected_rows());
/* z klauzulą where, która nigdy nie jest prawdziwa, powinno zrwócic 0 */
mysql_query('DELETE FROM mytable WHERE 0');
printf("Usuniętych rekordów: %d\n", mysql_affected_rows());
?>
Powyższy przykład wyświetli coś podobnego do:
Usuniętych rekordów: 10 Usuniętych rekordów: 0
Przykład #2 Przykład mysql_affected_rows() używający transakcję
<?php
$link = mysql_connect('localhost', 'mysql_user', 'mysql_password');
if (!$link) {
die('Nie można się połączyć: ' . mysql_error());
}
mysql_select_db('mydb');
/* Uaktualnienie rekordów */
mysql_query("UPDATE mytable SET used=1 WHERE id < 10");
printf ("Zaktualizowanych rekordów: %d\n", mysql_affected_rows());
mysql_query("COMMIT");
?>
Powyższy przykład wyświetli coś podobnego do:
Zaktualizowanych rekordów: 10
Notatki
Informacja: Transakcje
Jeśli używasz transakcji musisz wywołać mysql_affected_rows() po Twoim zapytaniu INSERT, UPDATE lub DELETE, a nie po COMMIT.
Informacja: Instrukcja SELECT
Aby uzyskać liczbę wierszy zwróconych przez SELECT, można użyć use mysql_num_rows().
Informacja: Kaskadowe klucze obce
mysql_affected_rows() nie zwraca liczby wierszy przetworzonych pośrednio przez użycie klauzuli ON DELETE CASCADE i/lub ON UPDATE CASCADE w ograniczeniach kluczy obcych.
Zobacz też:
- mysql_num_rows() - Zwraca liczbę wierszy w wyniku
- mysql_info() - Pobiera informacje o ostatnim zapytaniu
add a note
User Contributed Notes
mysql_affected_rows - [15 notes]
EToS ¶
5 years ago
HMax ¶
5 years ago
If you use "INSERT INTO ... ON DUPLICATE KEY UPDATE" syntax, mysql_affected_rows() will return you 2 if the UPDATE was made (just as it does with the "REPLACE INTO" syntax) and 1 if the INSERT was.
So if you use one SQL request to insert several rows at a time, and some are inserted, some are just updated, you won't get the real count.
sean at adtools dot co dot uk ¶
4 years ago
Here's a little function I've been using for a while now, pass it two parameters (action command (1 or 0 see notes)) and a sql statement.
It returns a simple line which shows the length of time taken to action the query, the status of the query (0= query not actioned, you can set this value for testing, 1=success qry executed successfully, -1= failed, there was a problem with the sql statement) the number of lines affected by that query and the sql statement itself.
I've found this invaluable when trying to tie down large amounts of updates to a table, using this you can easily see where a query was successfully executed and the number of rows are affected, or where there are problems and a statement has failed for example.
<?php
function dosql($action,$sql){
# assuming you have setup a link to your database entitled $link
# action = 1 run this query
# action = 0 don't run, just return sql statement
$start = getmtime();
if($action==1){
$result = mysql_query($sql);
$affectedrows = "[".mysql_affected_rows($link)."]";
}
return "[".number_format((getmtime()-$start),3)."][$action]: $sql\n";
mysql_free_result($result);
}
?>
Example output:
[0.072][1][80]: UPDATE MYTABLE SET FIELD = 1;
[0.106][1][758]: UPDATE ANOTHERTABLE SET FIELD = 2;
[0.006][-1][0]: UPDATER ANOTHERTABLE SET FIELD = 2;
The output shows:
[Timetaken][result]][lines affected]
The result will be either -1, 0 or 1, -1 means there's a problem with the sql statement, 1 means it executed correctly, 0 means it wasn't executed.
Ome Ko ¶
1 year ago
There are no rows affected by an update with identical data.
So here is one very ugly solution for these cases:
<?
function mysql_matched_rows() {
$_kaBoom=explode(' ',mysql_info());
return $_kaBoom[2];
}
?>
cbal at freemail dot hu ¶
1 year ago
I dont know why but sometimes mysql_affected_rows does not work (return 0 or nothing) besides the query worked well.
So use this if you have a problem:
<?php
$result = mysql_query("update/delete ...");
$last = mysql_query("SELECT ROW_COUNT();");
$last = mysql_fetch_array($last);
?>
PaulD ¶
3 years ago
Just a note: [you should] check for a mysql_affected_rows() return value of -1. If a series of queries were run as a transaction and one query failed, the logic in the foreach loop of the transaction() method in class MySQLDB will not issue a ROLLBACK. It may also be slightly more efficient to stop processing queries on the first failure.
dobrys at abv dot bg ¶
5 years ago
I see that when try to use mysql_affected_rows() with "mysql_pconnect(...)" without link indetifier as param in "mysql_affected_rows()" the result is allways -1.
When use link identifier "mysql_affected_rows($this_sql_connection)" - everything is Fine. This is is on PHP Version 5.2.0
Hope that this was helpfull for somebody
Typer85 at gmail dot com ¶
6 years ago
Just to clarify about the possible return values in this Manual those not familiar with PHP and MySQL.
"-1 indicates that the query returned an error."
-1 will be returned if the query itself can not be issued to the server, possibly because of syntax error AND if the last query was not either an Insert or Update statement.
mlugassy at 2find dot co dot il ¶
7 years ago
To solve the affectedRows() issue on MySQL using PEAR::DB, simply add a 'client_flags' key with a value of 2 to your $dsn options:
<?php
$dsn = array(
'phptype' => 'mysql',
'client_flags' => 2,
'username' => 'someuser',
'password' => 'apasswd',
'hostspec' => 'localhost',
'database' => 'thedb',
);
?>
temp02 at flexis dot com dot br ¶
7 years ago
SCENARIO
1. You're using MySQL 4.1x with foreign keys.
2. You have table t2 linked to table t1 by a CASCADE ON DELETE foreign key.
3. t2 has a UNIQUE key so that duplicate records are unacceptable.
3. You have a REPLACE query on t1 followed by an INSERT query on t2 and expect the second query to fail if there's an attempted insert of a duplicate record.
PROBLEM
You notice that the second query is not failing as you had expected even though the record being inserted is an exact duplicate of a record previously inserted.
CAUSE
When the first query (the REPLACE query) deletes a record from t1 in the first stage of the REPLACE operation, it cascades the delete to the record that would be duplicated in t2. The second query then does not fail because the "duplicate" record is no longer a duplicate, as the original one has just been deleted.
steffen at showsource dot dk ¶
8 years ago
Using OPTIMIZE TABLE will also return true.
So, if you want to check the numbers of deleted records, use mysql_affected_rows() before OPTIMIZE TABLE
deponti A_T tiscalinet D0T it ¶
9 years ago
It works also for REPLACE query,returning:
0 if the record it's already updated (0 record modified),
1 if the record it's new (1 record inserted),
2 if the record it's updated (2 operations: 1 deletion+ 1 insertion)
ben-xo at NOSPAMdubplatesNOSPAM dot org ¶
11 years ago
mysql_affected_rows() reports on the number of rows affected by an in-place operation on the database, but mysql_num_rows() returns the number of rows in a MySQL record set (which is held by PHP after MySQL has generated it). This means that if you can do
<?php
$a = mysql_query("SELECT ...");
$b = mysql_query("SELECT ...");
if (mysql_unm_rows($a) > mysql_num_rows($b)) print "a is larger";
else print "b is larger";
?>
... but this does not make sense for the operations supported by mysql_affected_rows(), which reports on the status of the database connection as a whole.
Particularly note this:
<?php
$query = "UPDATE ...";
mysql_query($query);
print mysql_affected_rows(); // more than 0
mysql_query($query); // same query twice
print mysql_affected_rows(); // 0.
?>
.. this is because the 2nd time you execute the identical query, all the rows are already updated so no rows are affected the 2nd time.
I hope this clears up why mysql_num_rows() and mysql_affected_rows() are fundamentally different
dfylstra at frontsys dot com ¶
11 years ago
mysql_affected_rows() also reports the number of rows changed by the LOAD DATA command. If you use the IGNORE option in LOAD DATA and you know the number of rows in the input file, you can use mysql_affected_rows() to determine the number of rows that were ignored.
info at fedushin dot ru ¶
3 years ago
mysql_affected_rows() DOES NOT count rows affected implicitly through 'ON DELETE CASCADE' and/or 'ON UPDATE CASCADE' foreign keys.
For example:
CREATE TABLE `types` (
`type` varchar(10) NOT NULL,
PRIMARY KEY (`type`)
) ENGINE=InnoDB;
CREATE TABLE `symbols` (
`symbol` char(1) NOT NULL,
`type` varchar(10) NOT NULL,
PRIMARY KEY (`symbol`),
KEY `FK_symbol_type` (`type`)
) ENGINE=InnoDB;
ALTER TABLE `symbols`
ADD CONSTRAINT `FK_symbol_type` FOREIGN KEY (`type`) REFERENCES `types` (`type`) ON DELETE CASCADE ON UPDATE CASCADE;
INSERT INTO `types` VALUES ('Number'), ('Letter');
INSERT INTO `symbols` VALUES ('1', 'Number'), ('2', 'Number'), ('A', 'Letter'), ('B', 'Letter');
<?php
mysql_query('UPDATE types SET type = "Digit" WHERE type = "Number"');
echo mysql_affected_rows() . '<br>';
mysql_query('DELETE FROM types WHERE type = "Letter"');
echo mysql_affected_rows() . '<br>';
?>
Each query actually affects 3 rows (= 1 type + 2 symbols), but output is:
1
1