I'm trying to loop through each row of a table in a database, then once I'm on a particular row get the value of a certain column. Is this possible? I've done a couple Google searches but nothing really concrete. I try using the mysqli_fetch_array() function but when I do I get the results of a column. I want to target each row. The code I have so far gets me the "nid" column. That's not what I want. I want to iterate through each row.
<?php
$serverName = "localhost";
$username = "user1";
$password = "sp#99#1";
$databaseName = "developer_site";
// Connection
$connection = new mysqli($serverName, $username, $password, $databaseName);
// Check Connection
if ($connection->connect_error) {
die("Connection failed:" . $connection->connect_error);
} // line ends if statement
$queryNodeRevision = "SELECT nid FROM node_revision";
// line above creates variable $queryNodeRevision > selects column "nid" from table "node_revision"
$results = mysqli_query($connection, $queryNodeRevision) or die("Bad Query: $results");
while ($row = mysqli_fetch_array($results)) {
echo "NID: ";
echo $row['nid'];
echo "<br/>";
}
?>
You can select rows by a certain condition with an SQL query alone and also select all columns.
SELECT * FROM node_revision where condition;
condition could be anything. For example another_row = 'something'.
But if, for some reason, you need to process the nid inside your php script to know if that row is the "particular" one you're searching, then you just select all the columns, or the ones you need.
$queryNodeRevision = "SELECT nid, col1, col2 FROM node_revision";
$results = mysqli_query($connection, $queryNodeRevision) or die("Bad Query: $results");
while ($row = mysqli_fetch_array($results)) {
if (condiiton) {
echo "Particular: ".$row['nid']
." ".$row['col1']
." ".$row['col2'];
}
}
condition could be something like $row['nid'] == 123 for example.
Hope it helps.
I have table named category which contain names of other tables in the same database. I want to fetch table names from category table and then fetch data from each table from db. So far I have this code below:
$db = new mysqli('localhost', 'root', '', 'db_cat');
if($db){
// $q = "SELECT TABLE";
// $echo = $db->query($q);
// echo $echo;
// $result = $db->query("SHOW TABLES");
$qCat="SELECT * FROM product_category";
$cat_query= $db->query($qCat) or die(mysql_error());
while ($fetch= $cat_query->fetch_object())
{
$cat_id=$fetch->id;
$category=$fetch->category;
$p_cat=str_replace(" ","_",strtolower($category).'_categories');
//if(strlen($category)>22){$fine_product_name= substr($service, 0,19).'...';}else{ $fine_product_name=$category;}
$result = $db->query("SHOW TABLES");
while($row = $result->fetch_array()){
$tables[] = $row[0];
}
}
The second query must be different.
$result = $db->query("SELECT * FROM $category");
while($row = $result->fetch_array()){
$tables[] = $row[0];
}
print_r($tables);
First of all your design to connect to a database is not that good, Please check the below code for a proper way of connecting to it.
<?php
$con=mysqli_connect("localhost","root","","db_cat");
//servername,username,password,dbname
if (mysqli_connect_errno())
{
echo "Failed to connect to MySql: ".mysqli_connect_error();
}
?>
Here is a sample code of getting data from a table ( where this table name is in another table).
$get_table_name ="SELECT TableName FROM table_name";
$get_name=mysqli_query($con,$get_table_name);
$count=0;
while($row_name=mysqli_fetch_array($get_name)){
$count++;
$tbName=$row_name['TableName'];
$_SESSION['table_name'][count]=$tbName;
}
This will show you how to fetch data from one table. You can use a For loop to get all the tables
$table=$_SESSION['table_name'][1];
$get_table ="SELECT * FROM $table";
.... // Normal way of fetching data
You can try to adjust your code according to this and improve it.
For further reference please refer http://php.net/manual/en/book.mysqli.php
I would like to know if the following is possible, and how:
I want to check if a username in my table appears in 5 or more rows
my table:
Example of usage that I want:
If the name (teste) is on more than 5 rows then do something..
Use HAVING, it allows you to filter by aggregated / manipulated fields
SELECT count(username) as shows_counter from tbl
group by username
HAVING count(username)>5
$check = mysql_query("SELECT count(name),name
FROM hack_log group by name HAVING count(name)>5");
$check = mysql_num_rows($result);// **Add this row**
if($check){ echo "HACKER!"; }else{ echo "not hacker"; }
Please use PDO or mysqli build-in objects
Accorging to your needs
You need to check number of rows
$db = new PDO('mysql:host=your_hostname;dbname=your_db;charset=UTF-8', $user, $pass);
$q = $db->prepare('SELECT count(name),name
FROM hack_log group by name HAVING count(name)>5');
$q->execute();
$rows = $q->fetchAll();
$res= count($rows)>0?"Hacker":"No Hacker";
echo $res;
How do I fetch only one value from a database using PHP?
I tried searching almost everywhere but don't seem to find solution for these
e.g., for what I am trying to do is
"SELECT name FROM TABLE
WHERE UNIQUE_ID=Some unique ID"
how about following php code:
$strSQL = "SELECT name FROM TABLE WHERE UNIQUE_ID=Some unique ID";
$result = mysql_query($strSQL) or die('SQL Error :: '.mysql_error());
$row = mysql_fetch_assoc($result);
echo $row['name'];
I hope it give ur desired name.
Steps:
1.) Prepare SQL Statement.
2.) Query db and store the resultset in a variable
3.) fetch the first row of resultset in next variable
4.) print the desire column
Here's the basic idea from start to finish:
<?php
$db = mysql_connect("mysql.mysite.com", "username", "password");
mysql_select_db("database", $db);
$result = mysql_query("SELECT name FROM TABLE WHERE UNIQUE_ID=Some unique ID");
$data = mysql_fetch_row($result);
echo $data["name"];
?>
You can fetch one value from the table using this query :
"SELECT name FROM TABLE WHERE UNIQUE_ID=Some unique ID limit 1"
Notice the use of limit 1 in the query. I hope it helps!!
$conn = new mysqli($servername, $username, $password, $dbname);
$sql = "SELECT name FROM TABLE WHERE UNIQUE_ID=Some unique ID";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// output data of each row
while($row = $result->fetch_assoc()) {
echo $row["name"]."<br>";
}
} else {
echo "0 results";
}
$conn->close();
What's the best way with PHP to read a single record from a MySQL database? E.g.:
SELECT id FROM games
I was trying to find an answer in the old questions, but had no luck.
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$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 :)