SOLVED: I knew there were fields that were empty that should have caught the check, but they were empty rather than NULL. So, when I was checking for NULL fields, it didn't find any.
I'm trying to check whether elements in a row with a specific name have any blank fields. I use it to find if any values are null, if there is, update and rows that were null. It isn't working properly though. I believe I have all the column names correct, I can't see what the problem is though. Here is my query:
//this goes through each row 1 by 1 and checks if an element is null
$stmt = $dbh->prepare("SELECT count(*) from csgo_item_list WHERE Item_Name =:itemname AND (Image_Link IS NULL OR Quantity IS NULL OR new_price IS NULL OR market_hash_name IS NULL OR last_update IS NULL OR is_tradable IS NULL OR old_price IS NULL OR item_type IS NULL OR skin_quality IS NULL OR skin_color IS NULL)");
//"$mydata->market_name" returns a valid name in the table
$stmt->bindValue(':itemname', $mydata->market_name);
$stmt->execute();
$count = $stmt->fetchColumn();
echo $count;
When I do this, some of the rows do have some null fields, yet when I echo $count it returns only 0's. This means I can't update my rows, because after the check I use the same line for an UPDATE:
if($count != 0){
$sql = $dbh->prepare("UPDATE csgo_item_list SET Quantity=:quantity, new_price=:newprice, Image_Link=:image_link, market_hash_name=:markethashname, last_update='1000-01-01 00:00:00', is_tradable='no', old_price=:oldprice, item_type=:type, , skin_quality=:skinquality, skin_color=:skincolor WHERE Item_Name=:itemname AND (Image_Link IS NULL OR Quantity IS NULL OR new_price IS NULL OR market_hash_name IS NULL OR last_update IS NULL OR is_tradable IS NULL OR old_price IS NULL OR item_type IS NULL OR skin_quality IS NULL OR skin_color IS NULL)");
I'll post an image of my database table, from what I've checked the names all match though:
http://gyazo.com/5ab3f2676c44eb696b02a38a64d9742a
Can anyone see why this isn't working?
I knew there were fields that were empty that should have caught the check, but they were empty rather than NULL. So, when I was checking for NULL fields, it didn't find any.
What I had to do was set all the empty columns to NULL:
UPDATE `table` SET `column` = NULL;
"....yet when I echo $count it returns only 0's. This mea...."
if($count != 0){ ....
if it is returning all '0's then why you are comparing "not equal" to 0 ?
it Should be if ($count == O){ I think.
I've looked around and have noticed a few people have had the same problem but their oversight doesn't seem to apply here.
I have a PHP function to add an array of values into a table. It first checks whether the values are empty and if so replaces them with NULL, in order to place a null in the table field. Each fields that I'm placing null into allows for null yet places a 0 there instead.
Here's some code:
public static function AddGame($array, $tId)
{
global $db; // Bring DB into scope
// Get IDs from particular names
$locId = $array['fLocation'];
// Ensure empty values are SQL null
$hTeamId = "'{$array['fHomeTeam']}'";
$vTeamId = "'{$array['fVisitTeam']}'";
$hScore = "'{$array['fHomeScore']}'";
$vScore = "'{$array['fVisitScore']}'";
$hHoldFor = "'{$array['fHomeHoldFor']}'";
$vHoldFor = "'{$array['fVisitHoldFor']}'";
// Prepare row for insertion
$row = "'','$tId','$locId',$hTeamId,$vTeamId,'{$array['fDate']}','{$array['fTime']}',$hScore,$vScore,'{$array['fGameType']}',$hHoldFor,$vHoldFor";
$stmt = $db->prepare("INSERT INTO `game` VALUES($row)");
if($stmt->execute()) return true;
else return false;
}
I've debugged this function at various lines and have dumped the $row string and it shows this, which is expected:
'','1','1','21','21','10/10/12','10:30AM','NULL','NULL','pool','NULL','NULL'
Yet when I check the table text type fields literally have the value NULL which is not what I want and also int fields show as 0. If I leave the values blank or as PHP's null then text fields show as empty (or properly null as I'd like) yet the ints still show as 0.
I expect this is only caused due to the way I insert the values indirectly.
Here is the SHOW CREATE TABLE game
CREATE TABLE `game` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`tId` int(11) NOT NULL,
`Lid` int(11) NOT NULL,
`hTeamId` int(11) DEFAULT NULL,
`vTeamId` int(11) DEFAULT NULL,
`date` text NOT NULL,
`time` text NOT NULL,
`hScore` int(11) DEFAULT NULL,
`vScore` int(11) DEFAULT NULL,
`type` text NOT NULL,
`hHoldFor` text,
`vHoldFor` text,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=17 DEFAULT CHARSET=latin1
UPDATE:
INSERT INTO `game` VALUES('','1','1','','','10/09/12','9:30AM','','','pool','winner of pool A','winner of pool B')
You are physically setting the value of the wanted NULL columns to a string of 'NULL'
NULL != 'NULL'
If you set your table structure for those columns to NULL, you can omit them from your query and they will automatically be NULL on insert.
Do this instead:
if(!empty($hHoldFor)) $hHoldFor = $array['fHomeHoldFor'];
Update
I was looking further into your example and there is a second point of failure.
$row = ... ",'$hHoldFor','$vHoldFor'";
The above line, if you set $hHoldFor = NULL, will insert quotes around NULL, turning it back into a string of NULL.
Try this:
if(!empty($hHoldFor)) $hHoldFor = "'{$array['fHomeHoldFor']}'";
...
$row = ... ",$hHoldFor,$vHoldFor";
This removes the single quotes around this value in the QUERY string and adds them to the variable itself.
Update 2
Here is an SQLFiddle using your schema. It returns NULL for NULL columns. Can you do an echo "INSERT INTOgameVALUES($row)"; and post the output? The issue is PHP is converting the NULL to 'NULL' still somewhere. This will help us get to the bottom of it.
Update 3
The issue is just as thought. Your PHP is inserting a blank string, '', into your database, which is not a NULL value. NULL is of a type, '' is a string with no length.
INSERT INTO `game` VALUES('','1','1','','','10/09/12','9:30AM','','','pool','winner of pool A','winner of pool B')
Try this:
public static function AddGame($array, $tId)
{
global $db; // Bring DB into scope
// Get IDs from particular names
$locId = $array['fLocation'];
// Ensure empty values are SQL null
$hTeamId = (strlen($array['fHomeTeam']) != 0 ? "'{$array['fHomeTeam']}'" : 'NULL');
$vTeamId = (strlen($array['fVisitTeam']) != 0 ? "'{$array['fVisitTeam']}'" : 'NULL');
$hScore = (strlen($array['fHomeScore']) != 0 ? "'{$array['fHomeScore']}'" : 'NULL');
$vScore = (strlen($array['fVisitScore']) != 0 ? "'{$array['fVisitScore']}'" : 'NULL');
$hHoldFor = (strlen($array['fHomeHoldFor']) != 0 ? "'{$array['fHomeHoldFor']}'" : 'NULL');
$vHoldFor = (strlen($array['fVisitHoldFor']) != 0 ? "'{$array['fVisitHoldFor']}'" : 'NULL');
// Prepare row for insertion
$row = "'','$tId','$locId',$hTeamId,$vTeamId,{$array['fDate']}','{$array['fTime']}',$hScore,$vScore,'{$array['fGameType']}',$hHoldFor,$vHoldFor";
$stmt = $db->prepare("INSERT INTO `game` VALUES($row)");
if($stmt->execute()) return true;
else return false;
}
You can't insert 'NULL'. Remove the single quotes around NULL.
Your string
'','1','1','21','21','10/10/12','10:30AM','NULL','NULL','pool','NULL','NULL'
Should look like
'','1','1','21','21','10/10/12','10:30AM',NULL,NULL,'pool',NULL,NULL
You should also define a column list whenever making an INSERT (ie. INSERT INTO table (col1, col2) VALUES ...)
Edit 1
I would recommend looking through your SHOW CREATE TABLE tbl_name
Edit 2
After testing this, I would still say the problem is with how you're inserting the data.
(18,1,1,21,21,'10/10/12','10:30AM',NULL,NULL,'pool',NULL,NULL)
Works.
('18','1','1','21','21','10/10/12','10:30AM','NULL','NULL','pool','NULL','NULL')
Does not work: Incorrect integer value: 'NULL' for column 'hScore' at row 1:
Edit 3
Here is an improved version of your class:
public static function AddGame($array, $tId)
{
global $db; // Bring DB into scope
// Get IDs from particular names
$locId = $array['fLocation'];
// Ensure empty values are SQL null
$hTeamId = empty($array['fHomeTeam']) ? 'NULL' : "'" . $array['fHomeTeam'] . "'";
$vTeamId = empty($array['fVisitTeam']) ? 'NULL' : "'" . $array['fVisitTeam'] . "'";
$hScore = empty($array['fHomeScore']) ? 'NULL' : "'" . $array['fHomeScore'] . "'";
$vScore = empty($array['fVisitScore']) ? 'NULL' : "'" . $array['fVisitScore'] . "'";
$hHoldFor = empty($array['fHomeHoldFor']) ? 'NULL' : "'" . $array['fHomeHoldFor'] . "'";
$vHoldFor = empty($array['fVisitHoldFor']) ? 'NULL' : "'" . $array['fVisitHoldFor'] . "'";
// Prepare row for insertion
$row = "$tId,$locId,$hTeamId,$vTeamId,'{$array['fDate']}','{$array['fTime']}',$hScore,$vScore,'{$array['fGameType']}',$hHoldFor,$vHoldFor";
$stmt = $db->prepare("INSERT INTO game (tId, Lid, hTeamId, vTeamId, date, time, hScore, vScore, type, hHoldFor, vHoldFor) VALUES($row)");
if($stmt->execute()) return true;
else return false;
}
Non-NULL values will be encased in quotes, otherwise they are assigned NULL. I've also defined the column list for INSERT and excluded id, as it's an AUTO_INCREMENT column.
Does you column allows NULL values? Check the DDL again maybe you have set the DEFAULT VALUE to zero.
When you try to insert null value in a column, don not wrap it with single quote. Example
INSERT INTO tableName (colName, ColNameB) VALUES (1, NULL)
In my case i had to display three situations: Case-empty, Case-yes and Case-no. I planned to use null, one and zero. But the null was being saved always as 0. The column i was working accepted null entries but all my nulls was being saved as zeros.
My solution, was considering Case-empty as zero, Case-yes as the number one and case-no as the number two. It is a workaround but solved the problem.
I have a column in a table which is has the data type of an integer. What I had in mind was that values added into that column will be either 0 - N, or just blank as in an empty variable (see below), but I'm not sure that this is possible?
if($resource) {
$resource = $id - 2;
} else {
$resource = "";
}
$result = mysql_query("INSERT INTO table (...,resource,...) VALUES (...,'$resource',...)");
If not, could I instead use the data type of VARCHAR, and then say:
if($resource) {
$resource = $id - 2;
} else {
$resource = "INVALID";
}
In that case, is there any conversion functions I'd have to do when extracting values from the column resource, or would numbers automatically be treated as integers?
If the field should be "white" for any reason, I think you should mark it as NULLABLE and use word NULL (not INVALID)
If a column is a number, never use a varchar, you will loose a lot of things (also, an int is smaller than a varchar)
EDIT 1: Code snippet to allow null values on column:
ALTER TABLE mytable MODIFY mycolumn INT;
If you specify it as:
ALTER TABLE mytable MODIFY mycolumn INT NOT NULL;
It will be not nullable, so it should be nullable by default if you didn't declare it differently
EDIT 2: Important note, the column must not be UNIQUE otherwise the value will be not nullable!
I have updated certain field in my database & that field has default value as NULL. How can I again fill NULL if field is emptied or deleted. As during this updation blank value is filled in database and of course that is not NULL. Is filling NULL instead of blank value good?
Using php how can I do that? Suppose I have condition if code
if(!empty($photo))
{ $a in database;
}
But in this condition if $photo is empty it will fill blank value of $a... Let me know to fill NULL in database.
You just have to write null, and not an empty value, to your database.
You SQL query would look like this :
update your_table
set your_field = NULL
where ...
instead of :
update your_table
set your_field = ''
where ...
To switch between those two queries, you might need some condition in your PHP code, depending on how it's organized ; maybe like this :
if (empty($photo)) {
// query to set the field to NULL
}
else {
// query to update the value
}
Note that if you have no value to store for a row in your database, you might also want to just delete that row :
delete from your_table
where ...
Of course, it's up to you to determine which is the best for your application : a row with a NULL value, or no row.