Thanks Livin Free...
Here's another one... Why is it that I always get the error message "Error: Can't open display:" in my mail whenever I execute or try to call an xterm command using cron to activate the command. What did I miss? Thanks in advance UNIX gurus... (3 Replies)
I'm currently looking into ways to integrate the Telegram API into the forums:
Telegram Bots - Bot Code Examples
I'm thinking, first off, to use the Telegram API to get forum alerts and notifications (to Bot or Not?).
Second, I thinking of ways to more deeply integrate Telegram into the... (5 Replies)
I have added a new experimental "Computer Science and Mathematics Trivia - True or False" section in the discussions, currently under the tags box.
In the future, I plan to
Expand this feature to add more trivia categories from math, science and technology.
Keep track of correct and... (20 Replies)
The UNIX and Linux Forums now has over 1000 TRUE / FALSE computer science and computer related trivia question in our database. These questions are of relatively high quality (compared to similar sites on the web) and are fun (according to feedback by users). In the first week during the... (1 Reply)
Thanks to Akshay, who helped me write the core MySQL queries, we now have two new draft leaderboards, by (1) member and by (2) country:
https://www.unix.com/trivia_stats.php
Currently milhan leads the members with a high score of 90%:
... (3 Replies)
Only a few days after I coded this new feature from scratch, we are seeing over 3000 entries in the database from members (mostly guests) playing CS trivia.
I have spend a lot of time coding this (from scratch) and testing the API. From the logs, it seems to have an API bug which appears... (31 Replies)
Today marks another milestone in the computer trivia app:
100,000 Computer Trivia Questions Answered by Users
Some notes to mention at this milestone:
vbe leads the "best score" category with 320 questions answered for an overall score of 91.2%.
rdrtx leads "most questions answered"... (0 Replies)
I have just completed the first phase of integrating all these devices and technologies:
MQTT, Node-RED, Linux, Apache2, MySQL, PHP, Telegram, ESP32, ESP8266, and the Arduino Uno
The glue that binds all this together is MQTT. In fact, MQTT makes this kind of integration nearly trivial to... (1 Reply)
Just noticed that our successful computer trivia feature (stats here) has surpassed over 50,000 questions answered by users:
https://www.unix.com/trivia_stats.php
This was a coding effort worth while and I'm pleased to see so many people enjoying it in such a short time since it was released... (3 Replies)
Discussion started by: Neo
3 Replies
LEARN ABOUT PHP
mysqli_rollback
MYSQLI_ROLLBACK(3) 1 MYSQLI_ROLLBACK(3)mysqli::rollback - Rolls back current transaction
Object oriented style
SYNOPSIS
bool mysqli::rollback ([int $flags], [string $name])
DESCRIPTION
Procedural style
bool mysqli_rollback (mysqli $link, [int $flags], [string $name])
Rollbacks the current transaction for the database.
PARAMETERS
o $
link -Procedural style only: A link identifier returned by mysqli_connect(3) or mysqli_init(3)
o $flags
- A bitmask of MYSQLI_TRANS_COR_* constants.
o $name
- If provided then ROLLBACK/*name*/ is executed.
RETURN VALUES
Returns TRUE on success or FALSE on failure.
CHANGELOG
+--------+-------------------------------------+
|Version | |
| | |
| | Description |
| | |
+--------+-------------------------------------+
| 5.5.0 | |
| | |
| | Added $flags and $name parameters. |
| | |
+--------+-------------------------------------+
EXAMPLES
Example #1
mysqli::rollback example
Object oriented style
<?php
$mysqli = new mysqli("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s
", mysqli_connect_error());
exit();
}
/* disable autocommit */
$mysqli->autocommit(FALSE);
$mysqli->query("CREATE TABLE myCity LIKE City");
$mysqli->query("ALTER TABLE myCity Type=InnoDB");
$mysqli->query("INSERT INTO myCity SELECT * FROM City LIMIT 50");
/* commit insert */
$mysqli->commit();
/* delete all rows */
$mysqli->query("DELETE FROM myCity");
if ($result = $mysqli->query("SELECT COUNT(*) FROM myCity")) {
$row = $result->fetch_row();
printf("%d rows in table myCity.
", $row[0]);
/* Free result */
$result->close();
}
/* Rollback */
$mysqli->rollback();
if ($result = $mysqli->query("SELECT COUNT(*) FROM myCity")) {
$row = $result->fetch_row();
printf("%d rows in table myCity (after rollback).
", $row[0]);
/* Free result */
$result->close();
}
/* Drop table myCity */
$mysqli->query("DROP TABLE myCity");
$mysqli->close();
?>
Procedural style
<?php
$link = mysqli_connect("localhost", "my_user", "my_password", "world");
/* check connection */
if (mysqli_connect_errno()) {
printf("Connect failed: %s
", mysqli_connect_error());
exit();
}
/* disable autocommit */
mysqli_autocommit($link, FALSE);
mysqli_query($link, "CREATE TABLE myCity LIKE City");
mysqli_query($link, "ALTER TABLE myCity Type=InnoDB");
mysqli_query($link, "INSERT INTO myCity SELECT * FROM City LIMIT 50");
/* commit insert */
mysqli_commit($link);
/* delete all rows */
mysqli_query($link, "DELETE FROM myCity");
if ($result = mysqli_query($link, "SELECT COUNT(*) FROM myCity")) {
$row = mysqli_fetch_row($result);
printf("%d rows in table myCity.
", $row[0]);
/* Free result */
mysqli_free_result($result);
}
/* Rollback */
mysqli_rollback($link);
if ($result = mysqli_query($link, "SELECT COUNT(*) FROM myCity")) {
$row = mysqli_fetch_row($result);
printf("%d rows in table myCity (after rollback).
", $row[0]);
/* Free result */
mysqli_free_result($result);
}
/* Drop table myCity */
mysqli_query($link, "DROP TABLE myCity");
mysqli_close($link);
?>
The above examples will output:
0 rows in table myCity.
50 rows in table myCity (after rollback).
SEE ALSO mysqli_begin_transaction(3), mysqli_commit(3), mysqli_autocommit(3), mysqli_release_savepoint(3).
PHP Documentation Group MYSQLI_ROLLBACK(3)