log a stock/share price variable to database useing php - php

Question

i have an API that retrieves stock price data through a PHP script. I have tried several different ways to add the price
to my database with no luck.
please help as this is driving me crazy, I have tried logging it as a float with different syntax but still doesn't display,
please could you be kind enough to give me an example using the code below as i am completely new to PHP/mysqli and programing in general.
thanks.
please note that I use import.io to create the API and have removed the API key.
This is how the API works:
<?PHP
$url = 'http://my api url.com';
$json =file_get_contents($url);
$retVal =json_decode($json, TRUE);
$output = "<ul>";
foreach($retVal['results'] as $results) {
$output .="<p>".$results['price/_source']."</p>";
}
$output .="</url>";
echo $output; // this would show the price like so: 1.139791
?> '
//this is the json file.
{
"offset": 0,
"results":
[
{
"price": "1.140 293"
}
`]`,
"cookies": [ ],
"connectorVersionGuid": "2af429a0-3fa4-4e67-b9bf-fbf453674ccb",
"connectorGuid": "87343523-d4c8-47db-b582-5408be1b679b",
"pageUrl": "http://www.x-rates.com/calculator/?from=EUR&to=USD&amount=1",
"outputProperties":
[
`{`
`"name": "price",`
`"type": "STRING"`
`}`
`]`
}