<?php
include('connection.php');
/* code for id goes here */
$q2= "select MAX(id) from usertable";
echo mysqli_query($sql,$q2);
$name=$_POST['name'];
$username=$_POST['usrname'];
$password=$_POST['psw'];
$dob=$_POST['date'];
$query="insert into usertable(name, username, password, dateofbirth) values('$name', '$username','$password','$dob')";
if(mysqli_query($sql,$query))
{
echo "Registered successfully";
}
?>
This is my insert command to register a user in my database. However the database contains a column named id which is the primary key. How do I fetch the id before executing the insert query so that it fetches the last id and increments it by 1 and inserts it in the db along with the other data. The id is numeric and I want the program to perform the operation itself rather than the user entering the data of the id. Please help.
You need to set your id field to auto incement and your database will do it automatically:
ALTER TABLE usertable MODIFY COLUMN id INT auto_increment;
You need to write a query
SELECT MAX(id) FROM usertable
and get the result from that and then increment that value by 1 and then set that value in id field.
Related
Is there a way to auto-increment in MYSQL after deleting a row from the database?
For example:
There is a table with 3 columns: StudentID, Student Name, and Contact details. Here StudentID will be the primary key which will keep incrementing after adding values in each column.
The PHP code will look as follows:
<?php
require_once "Delete_Form.php";
if ($_GET || id['id']) {
$id = mysqli_real_escape_string($db, $_GET['id']);
} else {
echo 'Value was not brought over';
}
echo $id;
$result = mysqli_query($db,"SELECT StudentID, StudentName, Contact FROM student WHERE
StudentID='$id'");
$row = mysqli_fetch_row($result);
$sql= "DELETE FROM `student` WHERE `student`.`studentID` = $id";
echo "<pre>\n$sql\n</pre>\n";
mysqli_query($db,$sql);
echo 'Success -Continue...';
return;
Once we delete an entry from the database the Auto-Incrementation of StudentID will mess up i.e if the last entry had a StudentID of 12 and then we delete the same then the next row we enter will have StudentID of 13.
We can always do ALTER TABLE `student` AUTO_INCREMENT = 1 which will reset it but that will solve the problem temporarily only.
Is there a way to add a PHP statement in the above code to reset auto increment whenever we delete a row?
Do it never.
Primary key in a table identifies the row uniquely during the whole table lifetime. Pay attention - TABLE lifetime, not ROW lifetime. The fact that the row was deleted changes nothing - the value identifies this deleted row nevertheless.
If you need rows enumeration without the gaps then create special column for this purposes or enumerate in a query.
PS. By the way, synthetic AI PK must be hidden for the user at all - this column destination is row identifying and foreign keys subsystem work. It must not have any additional meaning.
hello i tried using mysqli to fetch autoincrement id from the first table to insert it for second table, this is my database design for each table
Table users
id_user PK auto-inc
username
password
nama
role
status
table siswa
id_siswa PK auto-inc
id_tingkatan
nama_siswa
jk_siswa
hp_siswa
nama_ortu
jk_ortu
hp_ortu
id_user
this is what i have tried
$query = "INSERT INTO users
(username, password, nama, role, status)
VALUES ('$name','$password','$nama','$role','$status')";
$koneksi->query($query);
$query = "INSERT INTO siswa
(id_tingkatan, nama_siswa, jk_siswa, hp_siswa,
nama_ortu, jk_ortu, hp_ortu, id_user)
VALUES ('$tingkatan','$nama','$jksiswa','$hpsiswa',
'$namaortu','$hportu', $koneksi->insert_id)";
$koneksi->query($query);
the data is inserted into users table but not to siswa table, any suggestion to fix this?
edit : overlooked variable only ($jkortu) fixed now, thanks
In the latter INSERT, the number of items in the first commalist does not correspond with the number of items in the second commalist. This should throw a syntax error.
You are missing a parameter.
You should always test for mysql errors, otherwise it will fail silently, and you have no idea what is going on:
if (!$server->query($query)) {
throw new Exception($server->error());
}
I have a database of Users and another table for Teachers. Teachers have all the properties as a user but also an e-mail address. When inserting into the DB how can I insert the info, ensuring that the ID is the same for both?
the ID currently is on automatic incrament.
this is what I have at the moment:
$sqlQuery="INSERT INTO user(firstName,lastName,DOB,title,password,classRoomID)
VALUES('$myFirstName','$myLastName','$myDOB','$myTitle','$newPassword','$myClassRoom')";
$result=mysql_query($sqlQuery);
$sqlQuery = "INSERT INTO teacher(email) VALUES ('$myEmail')";
$result=mysql_query($sqlQuery);
thank you!
use MYSQL function LAST_INSERT_ID()
OR php mysql http://ro1.php.net/manual/en/function.mysql-insert-id.php
why to use separate table for teachers. instead, you can have email field with in user table and additional field with flag (T ( for teacher) and U (for user). Default can be a U. This have following Pros.
Will Not increase table size as email would be varchar
Remove extra overhead of maintaining two tables.
Same Id can be used
If you want to have that as separate table then answer you selected is good one but make sure last insert id is called in same connection call.
After the first insert, fetch the last inserted id:
$last_id = mysqli_insert_id(); // or mysql_insert_id() if you're using old code
Or you could expand your second query and use mysql's integrated LAST_INSERT_ID() function:
$sqlQuery = "INSERT INTO teacher(id, email) VALUES ((SELECT LAST_INSERT_ID()), '$myEmail')";
Try this:
$sqlQuery="INSERT INTO user(firstName,lastName,DOB,title,password,classRoomID)
VALUES('$myFirstName','$myLastName','$myDOB','$myTitle','$newPassword','$myClassRoom')";
$result=mysql_query($sqlQuery);
$id = mysql_insert_id();
$sqlQuery = "INSERT INTO teacher(id, email) VALUES (' $id ','$myEmail')";
$result=mysql_query($sqlQuery);
Insert data into two tables & using the same ID
First method
$sqlQuery1 = "INSERT INTO user(firstName,lastName,DOB,title,password,classRoomID) VALUES('$myFirstName','$myLastName','$myDOB','$myTitle','$newPassword','$myClassRoom')";
$result1 = mysqli_query($conn, $sqlQuery1);
$lastID = mysqli_insert_id($conn);
$sqlQuery2 = "INSERT INTO teacher(email, lastID) VALUES ('$myEmail', 'lastID')";
$result2 = mysqli_query($conn, $sqlQuery2);
If the first method not work then this is the second method for you
$sqlQuery1 = "INSERT INTO user(firstName,lastName,DOB,title,password,classRoomID) VALUES('$myFirstName','$myLastName','$myDOB','$myTitle','$newPassword','$myClassRoom')";
$result1 = mysqli_query($sqlQuery1);
$sqlQuery2 = "INSERT INTO teacher(email) VALUES ('$myEmail')";
$result2 = mysqli_query($sqlQuery2);
You can set the Foreign Key in your database table (phpMyAdmin/ MySQL Workbench) to let the Foreign Key follow the Primary Key (ID). Then the data after insert will auto-follow the Primary Key ID.
Example here,
Teachers table set ID - Primary Key
Users table set UserID - Foreign Key (will follow the Teachers table ID)
if you're using MySQL WorkBench, you can refer to this link to set a foreign key.
https://dev.mysql.com/doc/workbench/en/wb-table-editor-foreign-keys-tab.html
Hope I can help any of you.
Though you can use the LAST_INSERT_ID() function in order to get the last insert id, the best approach in this case is to create a column reference to user id table.
teacher
id | user_id | email
So the teacher.id could be anyting, but the user_id column is the real reference to user table.
If you use InnoDB table, you can make the database consistent using Foreign keys
You Should Use A Transaction In MySQL. First insert In One Table And GET LAST_INSERT_ID().
Insert LAST_INSERT_ID() In Second Table.
$sqlQuery="INSERT INTO user(firstName,lastName,DOB,title,password,classRoomID)
VALUES('$myFirstName','$myLastName','$myDOB','$myTitle','$newPassword','$myClassRoom')";
$sqlQuery = "INSERT INTO teacher(LAST_INSERT_ID(), email) VALUES (' $id ','$myEmail')";
$result=mysql_query($sqlQuery);
Suppose i have a database that store report from employees which first column is reportID(auto increment), staffID,name,department and so on.
Everytime i submit i report from my php page it will display increment number (reportID) in my php page. So lets say i got 3 report ID stored in the table, i want to delete three record, and then add 1 new record to the table, but now the reportID display as 4 because the past three reportID are 1,2,3, so how do i reset the new record to 1 instead of 4? is there a code to reset it?
This is my deletereport.php
<?php
include('adminconfig.php');
include('config.php');
$reportID = mysql_real_escape_string($_GET['id']);
$sql="DELETE FROM `report` WHERE `reportID`='$reportID'";
$result=mysql_query($sql);
if(!$result){
die('invalid query:'.mysql_error());
}
else
?>
<p style="font-family:arial;color:#0066CC;font-size:30px;">One row deleted...</p>
<?php
header('Refresh:3; url=viewreportdb.php');
die;
?>
You have to truncate the table to reset auto incremented values
or just
ALTER TABLE yourtable AUTO_INCREMENT = 1
similar discussion here
Auto Increment after delete in MySQL
Probably don't want to reset and just use auto-increment.
query following from PHP:
ALTER TABLE tablename AUTO_INCREMENT = 1
I want to insert a new row in my table. I want the id to be generated right automatically and not asked from the user. The user only provides title and text. I wrote this code in PHP:
<?php
$hostname = "localhost";
$database = "mydb";
$username = "myuser";
$password = "mypsw";
$link = mysql_connect( $hostname , $username , $password ) or
die("Attention! Problem with the connection : " . mysql_error());
if (!$link)
{
die('Could not connect: ' . mysql_error());
}
mysql_query("SET NAMES ‘utf8’",$link);
mysql_select_db("mydb", $link);
$lastid=mysql_insert_id();
$lastid=$lastid+1;
$sql="INSERT INTO announcements VALUES ('$lastid',CURDATE(),'$_POST[title]','$_POST[text]')";
if (!mysql_query($sql,$link))
{
die('Error: ' . mysql_error());
}
mysql_close($link);
header("Location: announcement.php");
?>
Sadly when I test it on my website, I get this error:
Error: Duplicate entry '0' for key 'PRIMARY'
Is mysql_insert_id() not working? What is wrong?
Don't do this. mysql will happily create an auto_increment column for you:
CREATE TABLE x (
id int not null primary key auto_increment
^^^^^^^^^^^^^^---add this to your PK field
);
INSERT INTO x (id) VALUES (null); // creates id = 1
INSERT INTO x (id) VALUES (null); // creates id = 2
mysql_insert_id() only returns the last id created by the CURRENT connection. You haven't inserted any data yet when you first run it, so you get back nothing.
Your version is incredibly vulnerable to race conditions. There is NO guarantee that the last ID you retrieve with mysql_insert_id() will not ALSO get retrieved by another copy of the script running in parallel, and get sniped out from under this copy of the script.
The primary key column on announcements should be auto_increment. When you do mysql_insert_id() it retrieves the id from the last query executed from that connection.
Because the INSERT is the query you are currently performing, it errors.
Try
INSERT INTO announcements
(date_field, title, text)
VALUES (CURDATE(),'$_POST[title]','$_POST[text]')
Just replace 'date_field', 'title', and 'text' with the applicable column names.
Alternatively the following should also work, as a NULL value in the AutoIncrement value should be acceptable
INSERT INTO announcements VALUES (NULL,CURDATE(),'$_POST[title]','$_POST[text]')
As mentioned in the other suggestion posted, you should make sure that the primary key field of the announcements table is set to be auto_increment.
Just for completion, you would use mysql_insert_id() when you want to use the id for the row you just inserted, i.e. if you then want to select the row you just inserted you could do
'SELECT * FROM announcements WHERE id = '.mysql_insert_id()
The problem is that you are asking for last insert id and you didn't inserted anything.
Convert your ID field in db to be autoincrement if its not.
Insert into database your announcment
Then ask for id using mysql_insert_id to get it.
But I see that you are not using it only when inserting then you don't need that functionality anyhow. Just insert without ID like this
"insert into announcements (InsertDate, Title, Text) VALUES (CURDATE(), '$_POST[title]', '$_POST[text]')";
and you should really be careful with your queries when using values from $_POST or $_GET or any other user typed value. There is possibility to execute SQLInjection through your form fields, so I suggest you to use mysql escape command or use parameters.
I hope this helps.
Assuming your table is set up properly, with the id field as AUTO_INCREMENT, you just need to perform an INSERT where you do not specify a value for id. That means you must specify the names of the columns you are inserting. So this line:
$sql="INSERT INTO announcements VALUES ('$lastid',CURDATE(),'$_POST[title]','$_POST[text]')";
becomes this
$sql="INSERT INTO announcements (`date`,`title`,`text`) VALUES (CURDATE(),'$_POST[title]','$_POST[text]')";
I guessed what your column names might be. Obviously they need to match your table definition.
If you do this, then the mysql_insert_id() function will return the id of the row you just inserted. (That is, it gives you the value of the previous insert, not the next one.)
You probably want to add "auto increment" to the table when creating it.
This will add an id automatically when inserting something.
e.g.
CREATE TABLE announcements
(
id int NOT NULL AUTO_INCREMENT,
PRIMARY KEY(id),
some_date int(11),
title varchar(200),
text varchar(3000)
);
mysql_insert_id "Retrieves the ID generated for an AUTO_INCREMENT column by the previous query " - http://php.net/manual/en/function.mysql-insert-id.php