So, I have pretty limited knowledge when it comes to mysql. Usually when dealing with content on our site, I'm used to loading it from expressionengine, our cms, which I know fine. But recently I have to update this page that loads its data directly from our database. I took a course on mysql a while back, but I still don't really know how to use it.
The page doesn't need to use too much information, its basically just a list of awards presented to different businesses. I assume the table on the database just has a column for Business name, City, Year, and Type of award won. Stuff like that.
Now accessing the database doesn't seem like it would be too hard, and I feel like I could google around and find what I need. But to get started, I would just like to see the actual table! Why is it so complicated of a procedure to do?
The code on the file that I'm working on was set up like this to access the database:
$user_name = "xxxxxxxxxx";
$password = "xxxxxxxxxx";
$server = "xxxxxxxxxx";
$database = "xxxxxxxxxx";
$conni = new mysqli($server, $user_name, $password, $database);
if (mysqli_connect_errno()) {
printf("<center>
<strong>No connection to database possible!<br />
Please contact us!</strong>
</center>");
exit();
}
I figured out how to view all tables on the database, by doing this:
$result = mysql_query("show tables");
while($table = mysql_fetch_array($result)) {
echo($table[0] . "<BR>");
}
So I know the name of the table I'm dealing with. I found a way to see all the column names:
$query = "select * from my_tablename";
$result = mysql_query($query);
$numcolumn = mysql_num_fields($result);
for ( $i = 0; $i < $numcolumn; $i++ ) {
$columnnames = mysql_field_name($result, $i);
echo $columnnames . "<br>";
}
But I still can't find how to just display the table itself. I might be thinking about this wrong, or not have the full idea, but what I want is a simple way to display the entire table, like with an html table. How can that be done?
You can build the <thead> of a table with the column names you have above, however to display the results in a table format, use the mysql_fetch_row function on the $result of SELECT * FROM my_tablename. To reuse the $result after you've got the field names as in your last block, use mysql_data_seek:
mysql_data_seek($result, 0);
And then you can iterate through your results to get the contents of the table:
while ($row = mysql_fetch_row($result)) {
echo '<tr>';
foreach ($row as $value) {
echo '<td>' . $value . '</td>';
}
echo '</tr>';
}
mysql_fetch_row will get a numerically indexed array with where each value is the column value in MySQL, therefore by running foreach you get the value of each column. Put it inside of a <td>, wrap it all in a <tr> and you have yourself a table!
Just for good measure, you should switch to using mysqli in PHP as the mysql_ functions are deprecated in later versions. To switch over, use the PHP documentation to search for the mysql_ functions you're currently using, there will be a pink message which will direct you to the mysqli equivalents
Related
Forgive me if my question sounds stupid as I'm a begginer with SQLite, but I'm looking for the simplest SQLite query PHP solution that will give me full text results from at least three separate SQLite databases.
Google seems to give me links to articles without examples and I have to start from somewhere.
I have three databases:
domains.db (url_table, title_table, date_added_table)
extras.db (same tables as the first db)
admin.db (url_table, admin_notes_table)
Now I need a PHP query script that will execute a query and give me results from domains.db but if there are matches also from extras.db and admin.db.
I'm trying to just grasp the basics of it and looking for a starting point where I can at least study and learn the first code.
First, you connect to 'domains.db', query what you need, save however you want, than if there were a result in the first query, you connect to the others and query them.
$db1 = new SQLite3('domains.db');
$results1 = $db1->query('SELECT bar FROM foo');
if ($results1->numColumns() && $results1->columnType(0) != SQLITE3_NULL) {
// have rows
// so, again, $result2 = $db2->query('query');
// ....
} else {
// zero rows
}
// You can work with the data like this
//while ($row = $results1->fetchArray()) {
// var_dump($row);
//}
Source:
http://php.net/manual/en/sqlite3.query.php
http://php.net/manual/en/class.sqlite3result.php
Edit.: A better approach would be to use PDO, you can find a lot of tutorials and help to use it.
$db = new PDO('sqlite:mydatabase.db');
$result = $db->query('SELECT * FROM MyTable');
foreach ($result as $row) {
echo 'Example content: ' . $row['column1'];
}
You can also check the row count:
$row_count = sqlite_num_rows($result);
Source: http://blog.digitalneurosurgeon.com/?p=947
I have a webpage written in HTML. I have a dropdown list that is populated by a database utilizing a MySQL query:
<SELECT NAME = "Participant" STYLE = "WIDTH: 187" TITLE="Begin typing participant last name for fast searching." required>
<OPTION SELECTED VALUE = "">Select Participant...</OPTION>
<?PHP
$allParticipants = getall_participants();
foreach($allParticipants as &$value) {
$dt = date('Y-m-d');
$val = $value->get_id();
$optval = $dt.$val;
echo "<OPTION VALUE='",$optval,"'>";
echo $value->get_first_name()," ",$value->get_last_name();
echo "</OPTION>";
}
?>
</SELECT>
The getall_participants() looks like:
function getall_participants () {
connect();
$query = "SELECT * FROM dbParticipants ORDER BY last_name";
$result = mysql_query ($query);
$theParticipant = array();
while ($result_row = mysql_fetch_assoc($result)) {
$theParticipant = new Participant($result_row['last_name'],
$result_row['first_name'], $result_row['address']);
$theParticipants[] = $theParticipant;
}
mysql_close();
return $theParticipants;
}
And on this same page I have a textbox that is pre-filled-in by another database:
<?php
$dt = date('Y-m-d');
$participants = getall_dbParticipantEntry_byDate($dt);
foreach($participants as &$value) {
$a = $a.$value.", ";
}
echo "<INPUT TYPE='text' NAME='Participants' STYLE='WIDTH:50px;' TITLE='Participants' ";
echo "VALUE='[", $a.' ', "]'/>";
?>
That getall_dbParticipantEntry_byDate($date) looks like:
function getall_dbParticipantEntry_byDate($date) {
connect();
$query = 'SELECT * FROM dbParticipantEntry WHERE date = "'.$date.'"';
$result = mysql_query ($query);
$theParticipantEntry = array();
while ($result_row = mysql_fetch_assoc($result)) {
$theParticipantEntry = new ParticipantEntry($result_row['date'], $result_row['id'], $result_row['call_time'],
$result_row['result'], $result_row['notes']);
$theParticipantEntries[] = $theParticipantEntry->get_id();
}
mysql_close();
return $theParticipantEntries;
}
However, while both of these functions work fine individually, when they're both on the same webpage (like I meant them to be), only the one that comes first runs. I tested this by switching them in and out. They both complete their designated tasks, but only when alone on the page.
How can I get them both to run and populate their respective fields?
Thanks so much.
Try the following order:
Connect to mySQL server
Do task 1
Do task 2
Close Connection
For me it looks, like you have closed the mysqlconnection, before you do task2.
Edit:
Maybe you can do it like that?
function f1 ()
{
$res = mysql_connect(...);
// .. do some queries ..
mysql_query($sql, $res);
mysql_close($res )
}
function f2 ()
{
$res = mysql_connect(...);
// .. do some queries ..
mysql_query($sql, $res);
mysql_close($res )
}
Edit:
From php.net:
Be careful when using multiple links to connect to same database (with same username). Unless you specify explicitly in mysql_connect() to create a new link, it will return an already open link. If that would be closed by mysql_close(), it will also (obviously) close the other connection, since the link is the same.
Had lot of trouble figuring it out, since in <=4.3.6 there was a bug which didn't close the connection, but after the patch to >=4.3.7, all my application broke down because of a single script that did this.
You run them both on the same connection. You need to store the resource id returned from mysql_connect and pass this to each mysql method (each uses it's own relevant resource).
that said, I think it is time to:
Move to something more modern like Mysqli or PDO extensions. Much better API
Use some kind of abstraction on the connection managment, preferably one instance of a DB managment class per connection. Plenty of examples on the web, and it is way above the scope of this site to provide such instructions.
Well i've been searching google, but I still can't find out how to do this.
I'm a beginner in php so i'm really stumped.
Anyways what I need to do is get all the data from a table and display it on my page.
Like
Contents of row 1
Contents of row 2
etc.
Well that's nice, get down voted for asking for help.
This might help you
print_r() displays information about a variable in a way that's readable by humans.
print_r(), var_dump() and var_export() will also show protected and private properties of objects with PHP 5. Static class members will not be shown.
Remember that print_r() will move the array pointer to the end. Use reset() to bring it back to beginning.
http://php.net/manual/en/function.print-r.php
This is pretty much PHP DB access 101
$pdo = new PDO('mysql:host=localhost;dbname=myDbName', 'username', 'password');
$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$stmt = $pdo->prepare('SELECT * FROM a_table');
$stmt->execute();
$resultSet = $stmt->fetchAll(PDO::FETCH_ASSOC);
foreach ($resultSet as $idx => $row) {
echo '<p>Contents of row ', $idx + 1, '</p><dl>';
foreach ($row as $col => $val) {
printf('<dt>%s</dt><dd>%s</dd>',
htmlspecialchars($col),
htmlspecialchars($val));
}
echo '</dl>';
}
I think google should have given you your answer since this is a rather easy to answer question, but when starting, you don't always know what to search for.
Anyways, hope this helps.
<?php
// connect with you database, returns boolean so you know if you succeeded or not
$con = mysql_connect($database,$username,$password);
if(!$scon){
die('Could not connect to database'); // Stop execution if connection fails
}
//create your query
$query = "Place your database query here";
//get the results
$result = mysql_query($query);
//now you want to go through each row of the result table and echo the contents, or
//use them for whatever reason
while($row = mysql_fetch_array($result)){
echo $row['field_you_want_to_display'];
echo $row['another_field_you_want_to_display']; //You see where this is going
}
//After doing what you want, close the connection to the database
mysql_close($con);
?>
Also, you may want to take a look at the documentation of php for find out what functions you have not seen before do.
I have two dynamic tables (tabx and taby) which are created and maintained through a php interface where columns can be added, deleted, renamed etc.
I want to read all columns simulataneously from the two tables like so;-
select * from tabx,taby where ... ;
I want to be able to tell from the result of the query whether each column came from either tabx or taby - is there a way to force mysql to return fully qualified column names e.g. tabx.col1, tabx.col2, taby.coln etc?
In PHP, you can get the field information from the result, like so (stolen from a project I wrote long ago):
/*
Similar to mysql_fetch_assoc(), this function returns an associative array
given a mysql resource, but prepends the table name (or table alias, if
used in the query) to the column name, effectively namespacing the column
names and allowing SELECTS for column names that would otherwise have collided
when building a row's associative array.
*/
function mysql_fetch_assoc_with_table_names($resource) {
// get a numerically indexed row, which includes all fields, even if their names collide
$row = mysql_fetch_row($resource);
if( ! $row)
return $row;
$result = array();
$size = count($row);
for($i = 0; $i < $size; $i++) {
// now fetch the field information
$info = mysql_fetch_field($resource, $i);
$table = $info->table;
$name = $info->name;
// and make an associative array, where the key is $table.$name
$result["$table.$name"] = $row[$i]; // e.g. $result["user.name"] = "Joe Schmoe";
}
return $result;
}
Then you can use it like this:
$resource = mysql_query("SELECT * FROM user JOIN question USING (user_id)");
while($row = mysql_fetch_assoc_with_table_names($resource)) {
echo $row['question.title'] . ' Asked by ' . $row['user.name'] . "\n";
}
So to answer your question directly, the table name data is always sent by MySQL -- It's up to the client to tell you where each column came from. If you really want MySQL to return each column name unambiguously, you will need to modify your queries to do the aliasing explicitly, like #Shabbyrobe suggested.
select * from tabx tx, taby ty where ... ;
Does:
SELECT tabx.*, taby.* FROM tabx, taby WHERE ...
work?
I'm left wondering what you are trying to accomplish. First of all, adding and removing columns from a table is a strange practice; it implies that the schema of your data is changing at run-time.
Furthermore, to query from the two tables at the same time, there should be some kind of relationship between them. Rows in one table should be correlated in some way with rows of the other table. If this is not the case, you're better off doing two separate SELECT queries.
The answer to your question has already been given: SELECT tablename.* to retrieve all the columns from the given table. This may or may not work correctly if there are columns with the same name in both tables; you should look that up in the documentation.
Could you give us more information on the problem you're trying to solve? I think there's a good chance you're going about this the wrong way.
Leaving aside any questions about why you might want to do this, and why you would want to do a cross join here at all, here's the best way I can come up with off the top of my head.
You could try doing an EXPLAIN on each table and build the select statement programatically from the result. Here's a poor example of a script which will give you a dynamically generated field list with aliases. This will increase the number of queries you perform though as each table in the dynamically generated query will cause an EXPLAIN query to be fired (although this could be mitigated with caching fairly easily).
<?php
$pdo = new PDO($dsn, $user, $pass, array(PDO::ATTR_ERRMODE=>PDO::ERRMODE_EXCEPTION));
function aliasFields($pdo, $table, $delim='__') {
$fields = array();
// gotta sanitise the table name - can't do it with prepared statement
$table = preg_replace('/[^A-z0-9_]/', "", $table);
foreach ($pdo->query("EXPLAIN `".$table."`") as $row) {
$fields[] = $table.'.'.$row['Field'].' as '.$table.$delim.$row['Field'];
}
return $fields;
}
$fieldAliases = array_merge(aliasFields($pdo, 'artist'), aliasFields($pdo, 'event'));
$query = 'SELECT '.implode(', ', $fieldAliases).' FROM artist, event';
echo $query;
The result is a query that looks like this, with the table and column name separated by two underscores (or whatever delimeter you like, see the third parameter to aliasFields()):
// ABOVE PROGRAM'S OUTPUT (assuming database exists)
SELECT artist__artist_id, artist__event_id, artist__artist_name, event__event_id, event__event_name FROM artist, event
From there, when you iterate over the results, you can just do an explode on each field name with the same delimeter to get the table name and field name.
John Douthat's answer is much better than the above. It would only be useful if the field metadata was not returned by the database, as PDO threatens may be the case with some drivers.
Here is a simple snippet for how to do what John suggetsted using PDO instead of mysql_*():
<?php
$pdo = new PDO($dsn, $user, $pass, array(PDO::ATTR_ERRMODE=>PDO::ERRMODE_EXCEPTION));
$query = 'SELECT artist.*, eventartist.* FROM artist, eventartist LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute();
while ($row = $stmt->fetch()) {
foreach ($row as $key=>$value) {
if (is_int($key)) {
$meta = $stmt->getColumnMeta($key);
echo $meta['table'].".".$meta['name']."<br />";
}
}
}
Hey, I am wondering how to extract the data from a table in a database onto a table in a page (users.php),
For example:
I want to be able to get all of the usernames and all the id's from my database onto a table.
So if I have in my database:
1 - Fred
2 - Frank
3 - Margret
It will see that I have them user's and id's in the database and print them onto a table.
Any help would be great,
Thanks.
Connect to your database. Host is the location, like localhost if its on your computer, or on the same server as your code. User and Password are self explanatory.
mysql_connect("host", "user", "pass");
The name of the database you want to access.
mysql_select_db("database");
The actual mysql query.
$result = mysql_query('SELECT `User_Name`, `User_ID` FROM TABLE');
Sort it into an array
while($temp = mysql_fetch_array($result)
{
$id = $temp['User_ID'];
$array[$id]['User_ID'] = $id;
$array[$id]['User_Name'] = $temp['User_Name'];
}
Turn the array into a table. (You could skip the last step and go right to this one.
$html ='<table><tr><td>User ID</td><td>User Name</td></tr>';
foreach($array as $id => $info)
{
$html .= '<tr><td>'.$info['User_ID'].'</td><td>'.$info['User_Name'].'</td></tr>';
}
echo $html . '</table>';
Or, the formatting you wanted
$html ='User Id - User Name';
foreach($array as $id => $info)
{
$html .= $info['User_ID'].' - '.$info['User_Name'].'<br>';
}
echo $html;
(For this answer, I will use the mysqli extension -- you could also want to use PDO ;; note that the mysql extension is old and should not be used for new applications)
You first have to connect to your database, using mysqli_connect (And you should test if the connection worked, with mysqli_connect_errno and/or mysqli_connect_error).
Then, you'll have to specifiy with which database you want to work, with mysqli_select_db.
Now, you can send an SQL query that will select all data from your users, with mysqli_query (And you can check for errors with mysqli_error and/or mysqli_errno).
That SQL query will most likely look like something like this :
select id, name
from your_user_table
order by name
And, now, you can fetch the data, using something like mysqli_fetch_assoc -- or some other function that works the same way, but can fetch data in some other form.
Once you have fetched your data, you can use them -- for instance, for display.
Read the pages of the manual I linked to : many of them include examples, that will allow you to learn more, especially about the way those functions should be used ;-)
For instance, there is a complete example on the page of mysqli_fetch_assoc, that does exactly what you want -- with countries insteand of users, but the idea is quite the same ^^
You can do something like the following (using the built-in PHP MySQL functions):
// assuming here you have already connected to the database
$query = "SELECT id,username FROM users";
$result = mysql_query($query, $db);
while ($row = mysql_fetch_array($result))
{
print $row["id"] . " - " . $row["username"] . "\n";
}
which will give you (for example):
1 - Fred
2 - Frank
3 - Margret
Where I've put the print statement, you can do whatever you feel like there eg put it into a table using standard HTML etc.