I've got a form with checkboxes set to bitwise values (CB1=1,CB2=2,CB3=4,CB4=8), and I want to store their sum in a single cell (to avoid having empty fields). The checkboxes have the same name but different values, and the data is sent to the processing php script as a serialised string, ie name=value&name=value2&name3=value3&name=&name=value5
Currently I can separate the string and get the values into the proper cells rather efficiently/easily. But, I'm wondering if there is a way to insert the first value into the cell then add subsequent values to the same cell. I imagine it would look something like this:
foreach ( $qaPairs as $pair ) {
list($question , $answer) = explode('=', $pair);
// ^ splits Q1=A1 into $question=Q1 and $answer=A1
// this mysql_query is a modified version of what I'm currently using
mysql_query("UPDATE $table SET `$question`=`$question`+'$answer' WHERE `key`='$key';") or die(mysql_error());
// $question is also the name of the column/field
} // end foreach
I dunno if it makes a difference, but: there are other datatypes (besides bitwise integers, such as text) and other form types (like textfields).
P.S. I would rather not have to somehow check if there are multiple instances of the same name and then do addition.
P.P.S. I got the UPDATE idea from this question: MySQL Batch increase value?, and I tried it out, but it didn't update null values (which I need it to do).
Thanks in advance!
Related
Sorry for my English but it is not my native language.
I have created a user interface to insert data to MySQL. Everything except one thing is ok but when I want to read data from multiple checkboxes and write them to SET type in MySQL it just doesn't work. I have tried to find the answer but after 4 hours I can't find it or I don't understand it.
http://jyxo.info/uploads/21/21b104df77f6ca723bb708d8d0549af5430e8e91.jpg
dobaVyskytu is SET type and there are in with month you can find mushroom(my tema is online atlas of mushrooms)
in user interfacei have 12 checkbox for 12 month.
http://jyxo.info/uploads/FD/fd548760b155307dfa677ada7c4be4996abf7b93.png
In dobavyskytu i need to have multiple select and that is reason why i use $doba +=
if(isset($_POST["Leden"]))
{
$doba += "Leden";
}
if(isset($_POST["Únor"]))
{
$doba += "Únor";
}
if(isset($_POST["Březen"]))
{
$doba += "Březen";
}
Db::query("INSERT INTO houby(nazev,dobaVyskytu,mistoVyskytu,popis,jedovatost,img)VALUES(?,?,?,?,?,?)",$nazev,$doba,$misto,$popis,$jedovatost,$foto);
Thank you all for reading and for help because it works now.
For strings in PHP, it uses . as concatanation not +, so
$doba .= "Leden";
Edit:
For a better way of doing this, you should try something like...
$options = [];
if(isset($_POST["Leden"]))
{
$options[] = "Leden";
}
if(isset($_POST["Únor"]))
{
$options[] = "Únor";
}
...
$doba = implode(',', $options);
As this will give you something like Leden,Únor
My hypotheses are:
$doba is the variable you want to insert in your SET type column (I translated and it seems the values you put as example in your question is Slovak for "January", "February", "March" -- I suppose there could be more).
I suppose that your SET type column is "dobaVyskytu" and that you created it correctly in MySQL by including all the possible values in the column definition.
(Your question update seem to confirm my hypotheses!)
First, when you want to insert multiple values in a SET type column in MySQL, the string value has to be separated with commas.
With the code I see, you can end up with that string "LedenÚnorBřezen" (I suppose you use += for string concatenation, but you should really use .= like Nigel Ren mentionned). You really want to end up with a string like "Leden,Únor,Březen" if all the 3 values you show are checked in your form.
See here for how to handle SET type in MySQL:
https://dev.mysql.com/doc/refman/5.7/en/set.html
Since you do not know if you will end up with 0 or multiple values for that column, I would suggest to make $doba an array.
$doba = array(); // depending on your PHP version, you can also write $doba = [];
After, you can add your values this way (the syntax $array[] = 'value' will apprend a value to the array):
$doba[] = "Leden";
$doba[] = "Únor";
$doba[] = "Březen";
Then, before inserting it, you can convert the array to a string with the values separated by commas that way:
$csvDoba = implode(',', $doba);
Then use $csvDoba instead of $doba in your Db::query() line.
After you get this working, here are more things you can look for to improve your code:
You can also take advantage PHP magic by naming your form checkbox with a special name to avoid repeating yourself.
For example, you can name all your checkboxes with the name "doba[]", and if (isset($_POST["doba"]), it will already be an array with all the checked values! But beware, if no value is checked, it won't be set. That way, you will avoid doing an if condition for each of your checkbox.
You can do something like this in your code to retrieve the value:
$doba = isset($_POST['doba']) ? (array) $_POST['doba'] : array();
What this do?
If any checkboxes named "doba[]" is checked, then you will retrieve them and make sure the value you retrieve is of type array, the "(array)" part for the value to be an array even if it was not (e.g., an error or someone trying to hack your form). Else you will return an empty array (as no choices has been put).
If you are not familar with this syntax, do a searcch for "ternary operator".
You will of course want to do some validation of your values if not already done
You might look to put the values in another table instead of using the "SET type", but that is up to you and at this stade you probably still have a couple stuff to learn, so I don't want to flood you with too much info. ;-)
usersim interested how do i select a text field form my mysql database, i have a table named users with a text field called "profile_fields" where addition user info is stored. How do i access it in php and make delete it? I want to delete unvalidate people.
PHP code
<?php
//Working connection made before assigned as $connection
$time = time();
$query_unactive_users = "DELETE FROM needed WHERE profile_fields['valid_until'] < $time"; //deletes user if the current time value is higher then the expiring date to validate
mysqli_query($connection , $query_unactive_users);
mysqli_close($connection);
?>
In phpmyadmin the field shows (choosen from a random user row):
a:1:{s:11:"valid_until";i:1370695666;}
Is " ... WHERE profile_fields['valid_until'] ..." the correct way?
Anyway, here's a very fragile solution using your knowledge of the string structure and a bit of SUBSTRING madness:
DELETE FROM needed WHERE SUBSTRING(
profile_fields,
LOCATE('"valid_until";i:', profile_fields) + 16,
LOCATE(';}', profile_fields) - LOCATE('"valid_until";i:', profile_fields) - 16
) < UNIX_TIMESTAMP();
But notice that if you add another "virtual field" after 'valid_until', that will break...
You can't do it in a SQL command in a simple and clean way. However, the string 'a:1:{s:11:"valid_until";i:1370695666;}' is simply a serialized PHP array.
Do this test:
print_r(unserialize('a:1:{s:11:"valid_until";i:1370695666;}'));
The output will be:
Array ( [valid_until] => 1370695666 )
So, if you do the following, you can retrieve your valid_until value:
$arrayProfileData = unserialize('a:1:{s:11:"valid_until";i:1370695666;}');
$validUntil = arrayProfileData['valid_until'];
So, a solution would be to select ALL items in the table, do a foreach loop, unserialize each "profile_fields" field as above, check the timestamp, and store the primary key of each registry to be deleted, in a separate array. At the end of the loop, do a single DELETE operation on all primary keys you stored in the loop. To do that, use implode(',', $arrayPKs).
It's not a very direct route, and depending on the number of registers, it may not be slow, but it's reliable.
Consider rixo's comment: if you can, put the "valid_until" in a separate column. Serializing data can be good for storage of non-regular data, but never use it to store data which you may need to apply SQL filters later.
I have to retrieve the history of a user and I have 4 tables whose data depend on each other.I can retrieve the data using loops,but I instead used the "where IN ()" clause and I implode the output of the previous query.However,if the list I provide to "where IN()" is empty it return an error.Is it that IN() cannot be empty?
When imploding an array for the IN clause, i do one of two things
1: Check if you even need to run the query at all
if(!empty($some_array)) {
//run mysql query
}
else {
// if you need to do something if the array is empty, such as error or set some defaults, do it here
}
2: A value in the array initiliser which is not ever in the database (for example, if im selecting based on a auto incrememnt id, i use zero as a default array value to stop any issues with empty data sets, as zero will never be in my id column).
$some_array = array(0);
You can add an empty value to the start, such as IN (0,your values here)
Basically, i have a working form where the user inputs details about their laptop to sell to my shop.
I give them a quote once they have submitted the Specs of the laptop.
At the moment i have got option boxes and checkboxes which each have a value-- for example these. ---
<label for="state">State</label><br>
<select name="state">
<option value="10">Excellent</option>
<option value="5">Good</option>
<option value="0">Poor</option>
</select><br>
The Values of the options they have selected get added up at the end and that gives them the quote - in the above example - "10" means £10 extra for a excellent condition laptop etc.
I use $_POST[state] to get the value of it to add onto the other options for the quote.
But my problem lies when i POST them to a database (so we can check when they come in).
When they get added to the database, obviously it just comes out as the values not the actually name of it like "excellent" or "good". just says "10" or "5".
Is there anyway to put the name of the option into the database instead of the value?
sure... just make sure that's what you want to do. It's usually not considered a good database practice to create denormalized tables like that, but you could do it. When you collect your post data, simply create another variable and assign a value to it based off the state value like so:
$stateText = '';
switch ($state){
case 10:
$stateText = 'Excellent';
break;
case 5:
$stateText = 'Good';
break;
case 0:
$stateText = 'Poor';
break;
default:
// bad value
$stateText = '';
}
...then store this to the database in a new column.
This is just one of many ways to do this.
You can only do it if you have a lookup, be it an array or in another table that stores the keys and values.
You should be carefuly not to store the post data directly into your database without sanitizing it, otherwise you might become subject to sql injection.
Is there anyway to put the name of the option into the database instead of the value?
There is, but it involves doing it explicitly (converting "10" into "Excellent" before inserting the value) rather than just basically tossing $_POST into the database as-is. You can make this very simple if you are building the <option>s with an array in the first place by reading the the array again and swapping the values with the keys.
$values = array(
10 => 'Excellent',
5 => 'Good',
0 => 'Poor',
);
$post_value = $_POST['state'];
$db_value = $values[$post_value];
// further validation: make sure the array key exists or use a default value
// further usage: build your HTML <options> with this array
However:
If you're going to do that, you're much better off storing the values as numbers and converting them to words when you display them (assuming the numbers do have some meaning). This also allows you to localize by providing translations.
Response to comments:
I would recommend a rating system, like 1 through 5, and calculate your price modifications internally - not directly from the user input or from a hardcoded value (in the database). This allows you to tweak the price changes from within your app, rather than from database values that were created at an earlier time, like if you decide an "Excellent" condition warrants an increase of 11 rather than 10 - unless you specifically want the prices "locked in" permanently at the time the product was posted.
Whatever you do, make sure to validate the input - I can't think of any good reason to use direct user input to calculate prices - it should be done internally based on product ids, and any other conditions. HTML source can be modified on-the-fly to post values you didn't expect from the dropdown.
You can't get it via the HTML form. But you can still do a server side that would map the values to the appropriate condition.
You can use a switch statement or an if statement to map them.
if(value == 10){
$condition = 'Excellent';
} else {//....}
Working on a pre-existing program that parses an html form that has a dynamically created number of fields, and in the interest of forward-compatibility, may not even know number of mysql columns...
I imagine that this requires creating two arrays, and comparing/re-ordering of some sort, but can't quite wrap my head around it...
Would this be something like:
A) Database Array -
1) get # of MySQL columns
2) loop through this number and get MySQL column names
B) Form Array -
1) get # of form fields
2) get form field names/values
C) Match Array -
match name.form_field[f] to name.mysql_column[c]
D) Execute Insert -
insert value of name.form_field[f] into name.mysql_column[c]
(INSERT INTO name.mysql_column[c], name.mysql_column[c+2], name.mysql_column[c+5], name.mysql_column[c+n] VALUES value(name.form_field[f]), value(name.form_field[f+9]), value(name.form_field[f+3]), value(name.form_field[f+x]))
I'm guessing the answer is something like the above, but can't quite picture the nested loops required to achieve the result...
Any possible solutions spring to mind out there?
All responses will be greatly appreciated!
Thanks,
Sean McKernan
McK66 Productions
This requires a longer answer, but I'll try a halfway decent introduction.
I suggest approaching the problem from the other direction. Ideally, the code would have it's own list of fields to insert and then go looking at the submitted data to construct the relevant rows. That also lets it have default values for 'missing' columns, so it can always generate row data with the correct number of fields.
There is a distressingly high amount of PHP which uses the submitted field names to build the SQL rather than starting with a known list of field names. In my experience, programmers do this because they are in control of the generated form, but forget that they aren't really in control of the submitted form. All it takes is a little editing in FireBug and you can knock the page for six, potentially corrupting your database.
I'm not sure if this fits your situation exactly, but we use something similar to the following for handling queries with data we aren't sure we have absolute control over. The form input names match the column names so if your's don't, you'll need to come up with the correct mapping.
This retrieves the column data from the table, and then builds the query from the form data using only the elements that match columns that exist in the table.
DB() is our wrapper around MDB2.
$db = new DB();
$sql = 'DESCRIBE `table`';
$result = $db->query($sql);
$row = array();
$query = array();
while ($row = $result->fetchRow())
{
if (array_key_exists($row['field'], $form_data))
if (is_null($form_data[$row['field']]))
$query[$row['field']] = 'NULL';
else
$query[$row['field']] = $db->quote($form_data[$row['field']]);
}
$keys = array_keys($query);
foreach ($keys as &$key)
$key = $db->quoteIdentifier($key);
unset($key);
$vals = array_values($query);
$sql = 'INSERT INTO `table` '
. '(' . implode(', ', $keys) . ') '
. 'VALUES(' . implode(', ', $vals) . ')';