Select all values from multiple tables - php

I am new to both mysql and php.
I have two tables which are 'members' and 'points'. Both of them including the column 'username'. I want to select all the values from these two tables where username= $POST[username].
So I wrote this but this is not working.
$username = $_POST['username'];
$sql = $con->prepare("SELECT *.members, *.points FROM members, points WHERE
username=?");
$sql->bind_param("s", $username);
$sql->execute();
$result = $sql->get_result();
$row = $result->fetch_assoc();
And I tried this :
$sql = $con->prepare("SELECT * FROM members INNER JOIN points
ON username.points = username.members WHERE username=?");
$sql->bind_param("s", $username);
$sql->execute();
$result = $sql->get_result();
$row = $result->fetch_assoc();
And this:
$sql = $con->prepare("SELECT *.points, *.members FROM members INNER JOIN points
ON username.points = username.members WHERE username=?");
$sql->bind_param("s", $username);
$sql->execute();
$result = $sql->get_result();
$row = $result->fetch_assoc();
I can't use UNION because the number of columbs are not equel in these tables.
So, Please help me what is wrong with the code? What is the proper way to select all from multiple tables.

Alias are meant to be used to specify to which table those column belong, so you need to prepend table name to your columns
SELECT * FROM members
INNER JOIN points
ON points.username = members.username
WHERE points.username = ?
You can otherwise assign an alias to your table while selecting and use them
SELECT * FROM members a
INNER JOIN points b
ON a.username = b.username
WHERE a.username = ?

You were close with this:
SELECT *.points, *.members
FROM members
INNER JOIN points ON username.points = username.members
WHERE username=?
Try this instead:
SELECT *
FROM members
INNER JOIN points ON members.username = points.username
WHERE members.username=?

check this
SELECT * FROM points,members WHERE points.username="'.$_POST['username'].'" AND members.username="'.$_POST['username'].'";
you can check this query it is very simple.

Related

Get applicants from Table 1 and compare id and get user details from Table 2 Using PHP

Ok so I have two Tables
Applicant list - this shows all applicants
User Table
Now I'm Providing news_id by Post method and I want to list details of all users(email,mobile,username) where the value for user_authToken and user_authtoken is same. Can Someone help me out with this logic using PHP.
$job_id = $_POST['job_id'];
$resultSet = $con->query("SELECT appliers_list.news_id AS jobid ,
appliers_list.user_authToken AS user,
user.user_name AS username,
user.mobile AS mobile,
FROM appliers_list,user
WHERE appliers_list.news_id = '$job_id'
ORDER BY appliers_list.id DESC
");
$rows = $resultSet->fetch_assoc();
First of all, your naming is very inconsistent, it's hard to read and understand.
Second, please use prepare statement, otherwise you open your system to SQL injection.
$news_id = $_POST['job_id'];
$stmt = $con->prepare("SELECT email, mobile, user_name
FROM users
WHERE user_authtoken in (select user_authToken from appliers_list where news_id = ?)");
$stmt->bind_param("i", $news_id);
$stmt->execute();
$resultSet = $stmt->get_result();
while($row = $resultSet->fetch_assoc()) {
// data manipulation here
}
you can use left join to get record from both table :
$job_id = !empty($_POST['job_id']) ? intval($_POST['job_id']) : 0;
$resultSet = $con->query("SELECT appliers_list.*,users.email
FROM appliers_list
left join users on appliers_list.user_authToken = users.user_authToken
WHERE news.news_id = '$job_id'
ORDER BY news.id DESC
");
$rows = $resultSet->fetch_assoc();
You didn't specify a relationship between the user and appliers_list tables, so you're getting all rows in user. You also have an extra comma at the end of the SELECT list.
$job_id = $_POST['job_id'];
$resultSet = $con->query("SELECT appliers_list.news_id AS jobid ,
appliers_list.user_authToken AS user,
user.user_name AS username,
user.mobile AS mobile
FROM appliers_list
JOIN user ON appliers_list.user_authToken = user.user_authToken
WHERE appliers_list.news_id = '$job_id'
ORDER BY appliers_list.id DESC
");
$rows = $resultSet->fetch_assoc();

How to get all the names of the tables involved in a sql query?

For example:
I have this query:
SELECT first_name
FROM users
INNER JOIN roles ON roles.id = users.id_roles
WHERE roles.name = 'admin';
I need an Array with the name of the tables used in the query,like that:
['users','roles'];
I think this would be tough using regex - unless you know your queries are all consistently following the same standard. Here's an option using EXPLAIN.
$tables = [];
$query = "EXPLAIN SELECT first_name FROM users INNER JOIN roles ON roles.id = users.id_rolesWHERE roles.name = 'admin'";
$q = mysqli_query($link, $query);
while($r = mysqli_fetch_assoc($q)) {
$tables[] = $r['table'];
}
print_r(array_unique($tables));

Cannot store SELECT query into PHP variable

I'm trying to store a query result in order to use it in another SELECT statement but it isn't working..
$username = $_SESSION['username'];
$result = "SELECT sensorid FROM users WHERE username = '$username' ";
$result is supposed to have an integer but how can I use that variable into another select like...
$sql = "SELECT * FROM sensor WHERE sensorid = '$result'";
You need to join users table with sensor table on sensorid column.
$query = "select s.* from users u join sensor s on s.id = u.sensorid where u.username = $username"
See this

How to search a word on two table if have or not by php query

I want to find out my userid from two table by username where username have already stayed in table2 or not. That means if username match in any table my query collect its userid.
table 1: username --- userid > john --- 100
table 2: username --- userid > colin --- 101
I read many article here nut I cannot understand what should I do.
Now think: I need john's uesrid,
So I tried:
$username = "john";
$q = "SELECT userid FROM table1,table2 WHERE table1.username = '$username' or table2.username = '$username'";
$result = mysqli_query($this->connection, $q);
From what i understand you want to check if the name already exist in one of your tables.
Here is the easy php code:
<?php
session_start();
include 'db_connect.php';
$check_1 = mysqli_query("SELECT * FROM Table_1 WHERE Username = '$Username'");
$check_2 = mysqli_query("SELECT * FROM Table_2 WHERE Username = '$Username'");
if(mysqli_num_rows($check_1)==0){
//Didnt exist in table 1
}
else if(mysqli_num_rows($check_2)==0){
//No result in table 2 either.
}
else{
//what you want to do if the username doesnt exist
}
Let me know how it worked out for you :)
You could select both userid fields and afterwards look if one of them is set:
$username = "john";
$q = "SELECT table1.userid AS userid1,table2.userid AS userid2 FROM table1,table2 WHERE table1.username = '$username' or table2.username = '$username'";
$result = mysqli_query($this->connection, $q);
Try this:
$username = "john";
$q = "SELECT table1.userid FROM table1 JOIN table2 ON table1.username=table2.username WHERE table1.username = '$username'";
$result = mysqli_query($this->connection, $q);
JOIN will join table2 to table1 if the maching pattern (table1.username=table2.username) equals true or exclude this row from table1 from results.
You can use UNION clause
$q="SELECT t1.userid FROM table1 as t1 WHERE username='$username' UNION SELECT t2.userid FROM table2 as t2 WHERE username='$username'";
You can use left join
$username = "username";
$q = "SELECT userid
FROM table1
LEFT JOIN table2 ON table1.username = table2.username
WHERE table1.username = '$username' or table2.username = '$username'";
$result = mysqli_query($this->connection, $q);

sql select from table then compare with other table in one statement

I have to tables in one database.
users
user_activate
I have to variables in php
$username = foo;
$key = jas823k123ksd34324;
Now I want to select from the table users the attribute user_id where user_username == $username
I do this with this statement
$sql = "SELECT user_id FROM users WHERE user_username = '$username'";
$result = mysqli_query($db, $sql);
while($row = mysqli_fetch_assoc($result)){
$user_id = $row['user_id'];
}
Now I want to select from the table user_activate the attribute user_activate_key where user_activate_key == $key;
For this I use this statement:
$sql2 = "SELECT user_activate_key FROM user_activate WHERE user_activate_key = '$key'";
$result2 = mysqli_query($db, $sql2);
while($row = mysqli_fetch_assoc($result)){
$user_key = row['user_activate_key'];
}
Can I do both statements in one statement?
As you've written it, two seperate queries is the correct way to do it. But I suspect that there's some kind of relationship between users and user_activate that might make what you're asking for make sense. Assuming that a user_activate_key is tied to a specific user_id, you could do something like the following:
select users.user_id, ua.user_activate_key
from users u
left join user_activate ua
on u.user_id = ua.user_id
and ua.user_activate_key = '$key'
where u.username = '$username'
The LEFT JOIN means that the user will be shown even if there isn't a matching user_activate_key record.

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