i am having a bit of issue with a mysql query. for some reason i can echo all all associated rows inside of the mysql query but outside of the query it only return the last row. here is my code. any suggestions?
//Get all associated
$q=mysql_query("SELECT * FROM `ACCOUNT` WHERE ACCOUNT_ID='$act_id'");
while ($row = mysql_fetch_assoc($q)){
$act_name=$row['ACT_NAME'];
echo "$act_name<br>"; // This returns all rows fine
}
echo "$act_name<br>"; // This only return the last row. i would like to get all rows.
The only way that you can fetch all of the records is by using PDO or MySQLi. Here is an example:
$conn = new mysqli($hostname, $username, $password, $database);
$query = "SELECT * FROM `ACCOUNT` WHERE ACCOUNT_ID='$act_id'";
$results = $conn->query($query);
$resultArray = $results->fetch_all(MYSQLI_ASSOC);
As #esqew said, you need to stop using the mysql_* functions.
Related
I've been spending a couple of hours trying to write mysqli queries to insert a new row in a database (with a primary key ID) and then select the ID of the new row. My code as it currently is:
<?php
include('connectionData.php');
$conn = mysqli_connect($server, $user, $pass, $dbname, $port)
or die('Connection error');
if(isset($_POST['submit'])) {
$pnum = $_POST['pnum'];
$phone_insert_text = "INSERT INTO `voterdatabase`.`phone` (`pnum`) VALUES (?)";
$phone_insert_query = $conn->prepare($phone_insert_text);
$phone_insert_query->bind_param('s', $pnum);
$phone_insert_query->execute();
$phone_select_text = "SELECT phone_id FROM voterdatabase.phone WHERE pnum=?";
$phone_select_query = $conn->prepare($phone_select_text);
$phone_select_query->bind_param('s', $pnum);
$phone_select_query->execute();
$phone_select_query->bind_result($phone_id);
echo $phone_id;
?>
$phone_insert_query executes without issue. But $phone_select_query doesn't appear to run at all, as echo $phone_id; has no effect. What might be going on here? I'm able to run the query directly in MySQLWorkbench.
Note that I previously tried doing this in one query using SELECT LAST_INSERT_ID();, but mysqli fails to execute any query containing that.
Please try this
$lastInsertID= mysqli_insert_id($conn);
Use insert_id property:
<?php
include('connectionData.php');
$conn = mysqli_connect($server, $user, $pass, $dbname, $port)
or die('Connection error');
if(isset($_POST['submit'])) {
$pnum = $_POST['pnum'];
$phone_insert_text = "INSERT INTO `voterdatabase`.`phone` (`pnum`) VALUES (?)";
$phone_insert_query = $conn->prepare($phone_insert_text);
$phone_insert_query->bind_param('s', $pnum);
$phone_insert_query->execute();
$phone_id = $conn->insert_id;
echo $phone_id;
?>
If you wish to be able to use the available functions to get the last inserted id, like mysqli_insert_id(), your table must have an AUTO_INCREMENT column. If not you will not get the id.
Also, even if you have the required columns, this will require two calls. To get around this, what you could do is something like create a stored procedure to do your insert for you and return the inserted id from the procedure.
this is for a homework assigment. I am suppose to: Demonstrate use of the SQL LIMIT clause by displaying only the first 3 matching rows from a query.
the "first 3 matching rows" part is throwing me off a bit. How do I match rows, or should I say find 3 matching rows. I know that in my table none of my rows 'match', its a simple table with 6 columns and 4 rows, I could add matching rows for demonstrating it.
I would be doing this using the PDO method via php obviously while using the sql limit statment to make it only 3 rows.
I figure a basis of the code would look something like this with a different sql statement.
php
$servername = "localhost";
$username = "";
$password = "";
$dbname = "";
try {
$conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
// set the PDO error mode to exception
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
// sql to delete a record
$sql = "****select * from teams where 3 rows match****";
// use exec() because no results are returned
$stmt = $conn->prepare($sql);
$stmt->execute()
}
catch(PDOException $e)
{
echo $sql . "<br>" . $e->getMessage();
}
$conn = null;
}
Just use SQL LIMIT
$sql = "select * from teams LIMIT 3";
$sql = "select * from teams [where condition(optional)] LIMIT 0,3";
where 0 means first row and 3 is number of rows you want
Refer http://www.w3schools.com/php/php_mysql_select_limit.asp
I am so sorry mybe it is a silly question but as I am new in web language and php I dont know how to solve this problem.
I have a code which is getting ID from user and then connecting to MySQL and get data of that ID number from database table and then show on webpage.
But I would like to what should I add to this code if user enter an ID which is not in table of database shows a message that no data found.
Here is my code:
<?php
//connect to the server
$connect = mysql_connect ("localhost","Test","Test") ;
//connection to the database
mysql_select_db ("Test") ;
//query the database
$ID = $_GET['Textbox'];
$query = mysql_query (" SELECT * FROM track WHERE Code = ('$ID') ");
//fetch the results / convert results into an array
$ID = $_GET['Textbox'];
WHILE($rows = mysql_fetch_array($query)) :
$ID = 'ID';
echo "<p style=\"font-color: #ff0000;\"> $ID </p>";
endwhile;
?>
Thank You.
Sorry if it is so silly question.
You should use PDO (great tutorial here: http://wiki.hashphp.org/PDO_Tutorial_for_MySQL_Developers ). This way, you can develop safer applications easier. You need to prepare the ID before inserting it to the query string, to avoid any user manipulation of the mysql query (it is called sql injection, guide: http://www.w3schools.com/sql/sql_injection.asp ).
The main answer to your question, after getting the results, you check if there is any row in the result, if you got no result, then there is no such an ID in the database. If you use PDO statements $stmt->rowCount();.
$db = new PDO('mysql:host=localhost;dbname=testdb;charset=utf8', 'username', 'password');
$stmt = $db->prepare("SELECT * FROM table WHERE Code=?");
$stmt->bindValue(1, $id, PDO::PARAM_INT); // or PDO::PARAM_STR
$stmt->execute();
$row_count = $stmt->rowCount();
if ($row_count > 0) {
$results = $stmt->fetchAll(PDO::FETCH_ASSOC);
//results are in $results
} else {
// no result, no such an ID, return the error to the user here.
}
Another reason to not use mysql_* functions: http://php.net/manual/en/migration55.deprecated.php
I am using nested queries to retrieve information from multiple tables. I need advice on optimizing this php code.
This function creates an object.
public function conn($query){
$mysqli = new mysqli('test','test','test','test');
$result = $mysqli->query("SET NAMES utf8");
$result = $mysqli->query("set character_set_client='utf8'");
$result = $mysqli->query("set collation_connection='utf8_general_ci'");
$result = $mysqli->query($query);
$mysqli->close();
return $result;
}
This code uses that function.
$connect = $this->conn("SELECT * FROM Table LIMIT 100000");
while($i = $connect->fetch_assoc()){
$name = $i["name"];
$connect2 = $this->conn("SELECT * FROM Names WHERE Name = '$name'");
if($connect2 ->num_rows > 0){
echo $name.'<br>';
}
}
Need recommendations for a connection to the database.
In the while loop, as you see, I am checking for the presence of $name in other table. But I am opening and closing a connection every time through the loop. And this will be 100001 connection opens and closes.
Is it possible to open a connection to the database only once?
P.S.: The SQL is an example - Please don't suggest changes there, because I am trying to figure out how to handle the repeated queries, not optimize the SQL.
Connection objects are reusable. Make a connection, then use it to make as many queries as you want. Close each query (that is, each result set) when you're done with it, then close the connection at the end of the run.
Closing a connection is a network operation, so it takes a while. Closing a query is mostly an in-memory operation, so it is faster.
In your example, you're using nested queries (more on that in a moment). Your code should end up looking something like this pseudocode:
public function getconn(){
$mysqli = new mysqli('test','test','test','test');
$mysqli->query("SET NAMES utf8");
$mysqli->query("set character_set_client='utf8'");
$mysqli->query("set collation_connection='utf8_general_ci'");
return $mysqli; /* return the connection handle */
}
$conn1 = getconn();
$conn2 = getconn();
$resultset1 = $conn1->query("SELECT * FROM Table LIMIT 100000");
while($i = $resultset1->fetch_assoc()){
$name = $i["name"];
$resultset2 = $conn2->query("SELECT * FROM Names WHERE Name = '$name'");
if($resultset2->num_rows > 0){
echo $name.'<br>';
}
$resultset2->close();
}
$resultset1->close();
$conn1->close();
$conn2->close();
(Please note; I haven't debugged this code.)
To take this optimization one step further, you should consider using a prepared statement for the query inside the while loop. Here's documentation on that http://php.net/manual/en/mysqli-stmt.fetch.php.
$conn1 = getconn();
$conn2 = getconn();
/* create a prepared statement with placeholder parameter ? */
$stmt = $mysqli->prepare("SELECT * FROM Name WHERE Name = ?"));
$name = '';
$name_out = '';
$stmt->bind_param("s", $name);
$stmt->bind_result($name_out);
$resultset1 = $conn1->query("SELECT * FROM Table LIMIT 100000");
while($i = $resultset1->fetch_assoc()){
$name = $i["name"];
$resultset2 = $stmt->execute(); /* run query with bound parameter */
if ($stmt_fetch() ( {
echo $name.'<br>';
}
$resultset2->close();
}
$resultset1->close();
$conn1->close();
$conn2->close();
(Please note; I haven't debugged this code either.)
Now, it's possible your pair of queries are just an example to show a set of nested queries. If so, that's fine. But, you are performing this task (retrieve 100K names) in an almost unimaginably inefficient way. You've said you don't want anybody to rewrite this query, but I am sorry, I can't just let this one pass.
This code would do a far more streamlined job.
$conn = getconn();
$q = "SELECT t.name FROM Table t JOIN Name n ON t.name = n.name LIMIT 100000";
$resultset = $conn->query($q);
while($i = $resultset->fetch_assoc()){
$name = $i["name"];
echo $name.'<br>';
}
$resultset->close();
$conn->close();
It's more efficient for two reasons. First, it doesn't use SELECT *, which ends up sending all sorts of data over the network from your MySQL server to your php program, just to throw it away.
Second, it doesn't use the nested queries. Instead, the JOIN query pulls all the name columns from Table that have a matching name column in Names.
The code below is an attempt to connect more than one database using PHP PDO and SQLite. No matter what I tried, it does not accept the select test1.table1. If I remove the database name the select works; so how do I reference more than one database in the select?
<?php
// connect to SQLite3 database
$query = "test1.sqlite3";
$db = new PDO("sqlite:$query");
// connect to second db
$query = "attach test2.sqlite3";
$db->query($query);
$query = "Select * FROM test1.table1 ";
$result = $db->query($query);
$rows = $result->fetchall(PDO::FETCH_ASSOC);
foreach ($rows as $row) {
echo "<pre>".print_r($row)."</pre>";
}
?>
The first database you connect to (test1.sqlite3 in your case) is always called main, regardless of the actual filename. Try SELECT * FROM main.table1.