MYSQLI - What is the best solution to split my data from mysqli_fetch_assoc? - mysqli

I would like to know what is the best way to split the data after a select all in a database with mysqli - please don't answer to add a where clause, because I can't in that situation, I NEED to manage data AFTER the query -.
So, I want to split the data in the mysqli_fetch_assoc.
What is the best method ? Is there a function to do that ? I need to do it manually with a for ? Is there an other easy solution to do it properly ?
Thanks for the help.
My code : (just an exemple, not the real code)
$select = "SELECT * FROM myTable";
$exec = mysqli_query($db, $select);
$rows = mysqli_fetch_assoc($exec);
// Now with a do while() I can display all the data
// But I want to display only 10 rows for exemple
// -> What is the best solution to split my data here ? <-
do{
// some html code here
}
while($rows = mysqli_fetch_assoc($exec))


Is there an other easy solution to do it properly ?
Definitely.
And it's fairly simple, and no WHERE clause required. Instead, you have to add LIMIT clause:
$select = "SELECT * FROM myTable LIMIT 10";
$exec = mysqli_query($db, $select);
while ($row = mysqli_fetch_assoc($exec)) {
// some html code here
}

Related

Question mark in laravel toSQL()

I get this output when trying to use toSQL() to debug my queries.
Laravel code:
$services = Service::latest()->where('status', '=', '0');
Output SQL:
"select * from `services` where `status` = ? order by `created_at` desc"
How can I get a proper query without ? mark? Thanks!

To view the data that will be substituted into the query string you can call the getBindings() function on the query like
below.
$query = User::first()->jobs();
dd($query->toSql(), $query->getBindings());
The array of bindings get substituted in the same order the ? appear in the SQL statement.
check this link

getting the 1st row in a database

I want to get the 1st row of the result depends on which build the room is. For example Building 1 have 1-200 rooms and Building 2 have 201-400 rooms. The code I tried is below. I have used the MIN in the where clause but I got all the rooms instead of having one.
$query = $this->db->query("SELECT * FROM `ha_utility_reading`");
if ($query->num_rows == 0) {
echo "some data match";
$lastroom = $this->db->select("*")->from("rooms")
->where("(SELECT MIN(room_num) FROM ha_rooms) and bldg_num = '$bldg_num'")
->get()->result_array();
foreach($lastroom as $key => $test) {
$output['room_num'][] = $test['room_num'];
json_encode($output);
}

You get all the rows because you need a group by clause. Anyway, the best way to do this is just adding this to your query:
order by room_num asc limit 1;

Try this,
select * from rooms order by room_num asc limit 1;

Column is not updating in postgresql

I tried to update my table like below:
$query = "select *
FROM sites s, companies c, tests t
WHERE t.test_siteid = s.site_id
AND c.company_id = s.site_companyid
AND t.test_typeid = '20' AND s.site_id = '1337'";
$queryrow = $db->query($query);
$results = $queryrow->as_array();
foreach($results as $key=>$val){
$update = "update tests set test_typeid = ? , test_testtype = ? where test_siteid = ?";
$queryrow = $db->query($update,array('10','Meter Calibration Semi Annual',$val->site_id));
}
The above code is working good. But in update query , The column test_typeid is not updated with '10'. Column test_typeid is updating with empty value. Other columns are updating good. I dont know why this column test_typeid is not updating? And the column test_typeid type is integer only. I am using postgreSql
And My table definition is:
What i did wrong with the code. Kindly advice me on this.
Thanks in advance.

First, learn to use proper JOIN syntax. Never use commas in the FROM clause; always use proper explicit JOIN syntax.
You can write the query in one statement:
update tests t
set test_typeid = '10',
test_testtype = 'Meter Calibration Semi Annual'
from sites s join
companies c
on c.company_id = s.site_companyid
where t.test_siteid = s.site_id and
t.test_typeid = 20 and s.site_id = 1337;
I assume the ids are numbers, so there is no need to use single quotes for the comparisons.

Modifying Columns In Zend Framework Select

In a Zend_Db_Select object, I am doing a join to get user information for some data records. For the join is on a userId, I would like to combine the user first and last name into a single column of name.
Basically I am looking to have something similar to this:
$table = array('u' => 'User');
$condition = 'u.id = t.id';
$columns = array('UserName' => 'u.FirstName + " " + u.LastName')
$select->joinLeft($table, $condition, $columns);
I have tried using a Zend_Db_Expr with no luck and the above does not work.
How would I go about doing this?

Zend_Db_Expr is the way to go, but you'll have better luck if you use the database's concatenation function. Assuming MySQL:
$columns = new Zend_Db_Expr("CONCAT(u.FirstName, ' ', u.LastName') AS name")

[zend][db] fetchAll with multiple variables

I'm trying to use fetchAll on a query that has 2 variables. I can't figure out the syntax.
I can manage with only 1 variable:
$sql = "SELECT * FROM mytable WHERE field1 = ?";
$this->_db->fetchAll($sql,$value1); # that works
However I'm having some issues when query has multiple variables
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$this->_db->fetchAll($sql,$value1,$value2); # doesn't work
$this->_db->fetchAll($sql,array("field1"=>$value1,"field2"=>$value2)); # doesn't work either
The reason why I want to use ? instead of placing the variables directly into the query is that I've learned that using ? allows for the query to be compiled generically by the db engine and improves performances.

There are two types of parameter, named parameters and positional parameters. You're mixing the two types and that won't work.
Named parameters match a placeholder by name. Names are started with the : symbol. The parameter names are not the same as the names of the columns you happen to use them for. You supply parameter values in an associative array, using the parameter name (not the column name) as the array keys. For example:
$sql = "SELECT * FROM mytable WHERE field1 = :param1 AND field2 = :param2";
$this->_db->fetchAll($sql,array("param1"=>$value1,"param2"=>$value2));
Positional parameters use the ? symbol for the placeholder. You supply parameter values using a simple (non-associative) array, and the order of values in the array must match the order of parameter placeholders in your query. For example:
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$this->_db->fetchAll($sql,array($value1,$value2));
Most brands of SQL database natively support only one style or the other, but PDO attempts to support both, by rewriting the SQL if necessary before preparing the query. Since Zend_Db is modeled after PDO, Zend_Db also supports both parameter styles.

This question is a bit old, but I thought I'd just add to it for reference sake.
I would recommend starting to use Zend_Db_Select with Zend_Db. I've been doing a lot with Zend_Db lately. More from Zend_Db_Select reference guide.
Lets assume you have a Zend_Db adapter: $this->_db
# this will get the Zend_Db_Select object
$select = $this->_db->select();
# now you build up your query with Zend_Db_Select functions
$select->from('mytable');
$select->where('field1 = ?', $field1);
$select->where('field2 = ?', $field2);
[...]
# echo to see the SQL (helps in debugging)
# SELECT * FROM mytable WHERE field1 = ? AND field2 = ? [...]
echo '<p>My SQL: ' . $select . '</p>';
# Execute the SQL / Fetch results
$results = $select->query()->fetchAll();
That's the basics from your given example, but the Zend Framework reference guide on the select object has a lot of good information on how to build even more complex queries with JOINS, UNIONS, GROUP BY, LIMIT, HAVING, etc.
If you wanted to use an alias name for a table or parameters, you use an associative array with the alias name being the index value:
# SELECT p.* FROM products AS p
$select->from('p' => 'products');
If you want to return only selected fields, you add an array of field names as a second parameter:
# SELECT model FROM products
$select->from(products, array(model));
Actually, the above could should produce fully qualified SQL as:
SELECT 'products'.model FROM 'products'
but I wrote the above for brevity and clarity in the example.
One thing I just came across is using AND and OR in the WHERE condition.
# WHERE a = $a
$select->where('a = ?', $a);
# WHERE a = $a AND b = $b
$select->where('a = ?', $a);
$select->where('b = ?', $b);
# WHERE a = $a OR b = $b
$select->where('a = ?', $a);
$select->orWhere('b = ?', $b);
# WHERE a = $a AND b = $b
$select->orWhere('a = ?', $a);
$select->where('b = ?', $b);
Notice, that whatever the following "where" function you use, will combine with the previous statement as that operand. Ok, that sounded confusing.
If the second "where" is an "OR" it will be an "OR" conditional. If the second "where" is a "AND" the statement will be "AND".
In other words, the first WHERE function is ignored in terms of what condition it will use.
In fact, I just asked a question on Stack Overflow yesterday regarding doing a complex WHERE using select.
Hope that helps!
Cheers!

Try this:
$sql = "SELECT * FROM mytable WHERE field1 = ? AND field2 = ?";
$statement = $this->_db->query($sql,array("field1"=>$value1,"field2"=>$value2));
$data = $statement->fetchAll();
$this->_db must be an instance of Db adapter.

Heres the actual Zend way to code for this.
$sql = "SELECT * FROM mytable WHERE field1 = :param1 AND field2 = :param2";
$this->_db->fetchAll($sql,array("param1"=>$value1,"param2"=>$value2));
$where = $this->_db->select()
->from('mytable')
->where('field1 = ?',$value1)
->where('field2 = ?',$value2);
$rowSet = $this->_db->fetchAll($where);
This works great for me