I wanted to get a list of all databases on a specific account on my server using PHP so I have used the following PHP/MySQL taken from this link: PHP - Get list of databases names
$db_conn = mysqli_connect('localhost', 'username', 'password');
//get a list of databases in the account
$result = mysqli_query($db_conn,"SHOW DATABASES");
//display results
while ($row = mysqli_fetch_array($result)) {
echo "database name - ".$row[0]."<br>";
}
This part works fine. But I now want to get the value of one specific row within a table in each of these databases, all databases contain exactly the same tables and therefore the same rows.
So inside the while { } I tried to put a SELECT statement:
$sql = "SELECT option_value FROM sweb_options WHERE option_name = 'siteurl'";
and then echoed $sql but this didn't do anything except output the statement. Any ideas how I can do this please?
Many thanks.
As I said in the comments
Well first of all you need FROM {database}.sweb_options
while ($row = mysqli_fetch_array($result)) {
$sql = "SELECT option_value FROM `{$row[0]}`.`sweb_options` WHERE option_name = 'siteurl'";
}
Otherwise it will use whatever database you connected to with this instance of mysqli
So basically that just tells it which one you want. You can also do Joins and Unions across multiple DB in MySQL this is not true of all Databases though. Something to keep in mind more if you were using PDO instead of mysqli, but still worth mentioning.
Cheers.
Something like this should work:
while ($row = mysqli_fetch_array($result)) {
$sql = "SELECT option_value FROM {$row[0]}.sweb_options WHERE option_name = 'siteurl'";
$result2 = mysqli_query($db_conn, $sql);
// check for success in case table doesn't have option_value column
if ($result2) {
$row2 = mysqli_fetch_assoc($result2);
echo $row2['option_value'];
}
}
I need to count the number of instances of a word in a column from my database and then get a true or false result depending on if it exceeds 36 instances. I use wordpress and I know that the connecction to the database is correct. And I am using wordpress.
This is what I got this far but its not working:
$selected = mysql_select_db("bringes_phpbb3", $dbConn) or die("Could not select database. The error was ".mysql_error());
mysql_query("SET NAMES utf8");
$SQL_COUNT ="SELECT COUNT(field_name) AS total_number FROM cyklister WHERE grupp LIKE CONCAT ('%','word','%')";
$result = mysql_query($SQL_COUNT);
if ($result >= 36){
$awnser = true;
mysql_free_result($result);
mysql_close($dbConn);
The SQL query is not complete or may be far from what I am looking for. Can someone help me?
After executing mysql_query, you need to call mysql_fetch_array to retrieve the result:
$result = mysql_query($SQL_COUNT);
$row = mysql_fetch_array($result);
$count = $row[0];
if ($count >= 36) {
$awnser = true;
}
How do I show the results for $wordavg in php. I have done the query in SQL on database after taking out variables so I believe the query is correct but don't know how to show the results of the search in php.
$usertable = 'words';
$yourfield = 'wordname';
$query = "SELECT AVG(CHAR_LENGTH( wordname)) AS $wordavg FROM $usertable WHERE $yourfield LIKE '"."$current_letter"."%' ";
$result = mysql_query($query);
First, you should be using mysqli instead. Back to your question, usually you can iterate over a result with a loop as follows:
while ($row = mysql_fetch_assoc($result)) {
echo $row['field'];
}
More info and examples in the PHP mysql_query doc.
Since you only have one row of data to return, you don't need the loop part. You can simply use
$row = mysql_fetch_assoc($result);
$wordavg = $row['wordavg'];
You shouldn't have the $ in wordavg in your query. It should be just ...AS wordavg FROM...
I've been struggling with this problem for a couple of days and can't make any progress...
I'm trying to get just ONE result from my database but on contrary I'm getting the whole table : (
php:
{
$connect = #mysqli_connect ($host, $username, $pass, $dbname)
OR die ('Could not connect to MySQL');
$table = $_REQUEST['table'];
$key = $_REQUEST['id'];
$key_value = $_REQUEST['id_value'];
$q = "SELECT * FROM ".$table." where ".$key."='".$key_value."'";
$r = #mysqli_query ($connect, $q);
while ($row = mysqli_fetch_array($r))
$output[]=$row;
print(json_encode($output));
}
I think there's no need to show you my android code for that since the data is received well (also updating tables works fine) ... all i want is to get that ONE result from my DB.
When simply navigating to this file on the browser there's no problem obviously...
Thanks in advance, cheers
You are doing something like where 1 = 1 and that is always true. You are not naming your column. You are replacing that with a number.
try this (unverified):
"SELECT * FROM ".$table." where id='".$id."'";
If you want to get just the first row of the results, then you have two options:
include LIMIT in your query (preferred solution)
SELECT * FROM ".$table." where ".$id."='".$id."' LIMIT 1"
don't loop to get all the data, simply read the first row and return it.
$table = $_REQUEST['table'];
$key = $_REQUEST['id'];
$key_value = $_REQUEST['id_value'];
$q = "SELECT * FROM ".$table." where ".$id."='".$id."'";
You're assigning $key and $key_value but then using $id.
you are setting your condition to where ".$id."='".$id."'";, so, if you pass id=1, that will mean: WHERE 1=1, and that is always true. that's why it's returning all the records.
What's the best way with PHP to read a single record from a MySQL database? E.g.:
SELECT id FROM games
I was trying to find an answer in the old questions, but had no luck.
This post is marked obsolete because the content is out of date. It is not currently accepting new interactions.
$id = mysql_result(mysql_query("SELECT id FROM games LIMIT 1"),0);
$link = mysql_connect('localhost','root','yourPassword')
mysql_select_db('database_name', $link);
$sql = 'SELECT id FROM games LIMIT 1';
$result = mysql_query($sql, $link) or die(mysql_error());
$row = mysql_fetch_assoc($result);
print_r($row);
There were few things missing in ChrisAD answer. After connecting to mysql it's crucial to select database and also die() statement allows you to see errors if they occur.
Be carefull it works only if you have 1 record in the database, because otherwise you need to add WHERE id=xx or something similar to get only one row and not more. Also you can access your id like $row['id']
Using PDO you could do something like this:
$db = new PDO('mysql:host=hostname;dbname=dbname', 'username', 'password');
$stmt = $db->query('select id from games where ...');
$id = $stmt->fetchColumn(0);
if ($id !== false) {
echo $id;
}
You obviously should also check whether PDO::query() executes the query OK (either by checking the result or telling PDO to throw exceptions instead)
Assuming you are using an auto-incrementing primary key, which is the normal way to do things, then you can access the key value of the last row you put into the database with:
$userID = mysqli_insert_id($link);
otherwise, you'll have to know more specifics about the row you are trying to find, such as email address. Without knowing your table structure, we can't be more specific.
Either way, to limit your SELECT query, use a WHERE statement like this:
(Generic Example)
$getID = mysqli_fetch_assoc(mysqli_query($link, "SELECT userID FROM users WHERE something = 'unique'"));
$userID = $getID['userID'];
(Specific example)
Or a more specific example:
$getID = mysqli_fetch_assoc(mysqli_query($link, "SELECT userID FROM users WHERE userID = 1"));
$userID = $getID['userID'];
Warning! Your SQL isn't a good idea, because it will select all rows (no WHERE clause assumes "WHERE 1"!) and clog your application if you have a large number of rows. (What's the point of selecting 1,000 rows when 1 will do?) So instead, when selecting only one row, make sure you specify the LIMIT clause:
$sql = "SELECT id FROM games LIMIT 1"; // Select ONLY one, instead of all
$result = $db->query($sql);
$row = $result->fetch_assoc();
echo 'Game ID: '.$row['id'];
This difference requires MySQL to select only the first matching record, so ordering the table is important or you ought to use a WHERE clause. However, it's a whole lot less memory and time to find that one record, than to get every record and output row number one.
One more answer for object oriented style. Found this solution for me:
$id = $dbh->query("SELECT id FROM mytable WHERE mycolumn = 'foo'")->fetch_object()->id;
gives back just one id. Verify that your design ensures you got the right one.
First you connect to your database. Then you build the query string. Then you launch the query and store the result, and finally you fetch what rows you want from the result by using one of the fetch methods.
$link = mysql_connect('localhost','root','yourPassword')
mysql_select_db('database',$link);
$sql = 'SELECT id FROM games'
$result = mysql_query($sql,$link);
$singleRow = mysql_fetch_array($result)
echo $singleRow;
Edit: So sorry, forgot the database connection. Added it now
'Best way' aside some usual ways of retrieving a single record from the database with PHP go like that:
with mysqli
$sql = "SELECT id, name, producer FROM games WHERE user_id = 1";
$result = $db->query($sql);
$row = $result->fetch_row();
with Zend Framework
//Inside the table class
$select = $this->select()->where('user_id = ?', 1);
$row = $this->fetchRow($select);
The easiest way is to use mysql_result.
I copied some of the code below from other answers to save time.
$link = mysql_connect('localhost','root','yourPassword')
mysql_select_db('database',$link);
$sql = 'SELECT id FROM games'
$result = mysql_query($sql,$link);
$num_rows = mysql_num_rows($result);
// i is the row number and will be 0 through $num_rows-1
for ($i = 0; $i < $num_rows; $i++) {
$value = mysql_result($result, i, 'id');
echo 'Row ', i, ': ', $value, "\n";
}
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$db = new mysqli('localhost', 'tmp', 'tmp', 'your_db');
$db->set_charset('utf8mb4');
if($row = $db->query("SELECT id FROM games LIMIT 1")->fetch_row()) { //NULL or array
$id = $row[0];
}
I agree that mysql_result is the easy way to retrieve contents of one cell from a MySQL result set. Tiny code:
$r = mysql_query('SELECT id FROM table') or die(mysql_error());
if (mysql_num_rows($r) > 0) {
echo mysql_result($r); // will output first ID
echo mysql_result($r, 1); // will ouput second ID
}
Easy way to Fetch Single Record from MySQL Database by using PHP List
The SQL Query is SELECT user_name from user_table WHERE user_id = 6
The PHP Code for the above Query is
$sql_select = "";
$sql_select .= "SELECT ";
$sql_select .= " user_name ";
$sql_select .= "FROM user_table ";
$sql_select .= "WHERE user_id = 6" ;
$rs_id = mysql_query($sql_select, $link) or die(mysql_error());
list($userName) = mysql_fetch_row($rs_id);
Note: The List Concept should be applicable for Single Row Fetching not for Multiple Rows
Better if SQL will be optimized with addion of LIMIT 1 in the end:
$query = "select id from games LIMIT 1";
SO ANSWER IS (works on php 5.6.3):
If you want to get first item of first row(even if it is not ID column):
queryExec($query) -> fetch_array()[0];
If you want to get first row(single item from DB)
queryExec($query) -> fetch_assoc();
If you want to some exact column from first row
queryExec($query) -> fetch_assoc()['columnName'];
or need to fix query and use first written way :)