How to detect if a mysql database column contains text or is empty

Question

Basically, I am wanting to detect if a database column is empty or if it contains text. The text doesn't have to be a specific set text just text.

If the column is empty, then show a message in php.

I have tried to use the row in question but still learning php so not quite sure the way around this.

if ($row['insert_time'] contains "") then {echo "The row contains no text"};

If the column insert_time contains no text, I want it to display "No Results" or something to let the user know there's no text.

If the column insert_time contains text, then it will display the rest of the function I have found useful in my case.

I am connecting to the database using the following;

```

$link = mysqli_connect("localhost", "root", "", "chaotic");
if($link === false){
    die("ERROR: Could not connect. " . mysqli_connect_error() . " Please enter correct details in the install/config file.");
}

?> ```

The insert_time is however set for date and time, but with the database export file I was given to test with, contains 2 entries with no insert_time. So in future reference instead of PHP displaying it as an empty table row, I want to let user's know that the status is Unknown or similar.

What I also forgot to mention, is I am using a script from the web for "Facebook Time Ago" function, Its setup correctly but if the empty database column contains nothing, it automatically sets the table row to 46 Years.

What is the MySQL type of the `insert_time` column? If it be a date and you have it set to be not nullable, then it can never be empty. — Tim Biegeleisen, Dec 26 '18 at 08:11
How are you connecting to the DB? mysqli? pdo? using another abstraction layer as doctrine? write the code you are using for you DB query within your question. — yivi, Dec 26 '18 at 08:12
What do you use to disconnect/close the connection - or do you leave it hanging with resources in use? — Wilson Hauck, Dec 26 '18 at 13:09

score 1 · Answer 1 · answered Dec 26 '18 at 08:13

1

You want to check condtion with php like

if (isset($row['insert_time']) && $row['insert_time'] != ''){ 
    echo $row['insert_time']; 
}else{
    echo "The row contains no text";
};

answered Dec 26 '18 at 08:13

Ravi Chauhan

1,409
13
26

Kagiso Marvin Molekwa · Accepted Answer · 2018-12-26T08:50:22.377

1

Since values returned from the database are always strings (except if they are NULL), you can check if the length of the value is 0 or more characters.
And because of PHP's weak typing an if statement like this...

if ($row['insert_time'] == "") { }

Will actually become true even when $row['insert_time'] contains the value of 0 (AKA non empty).

So it is best to perform your evaluation based on the first point above (checking the length of the value). Like so...

if (strlen($row['insert_time']) > 0) { 
    echo $row['insert_time']; 
}
else {
    echo "No Results";
};

edited Dec 26 '18 at 08:50

answered Dec 26 '18 at 08:24

Kagiso Marvin Molekwa

915
1
9
25

1

The issue of typing is one that can be solved... https://stackoverflow.com/a/25692758/362536 I was shocked to see that this is still an issue by default. Haven't had to deal with it in many years. :-) – Brad Dec 27 '18 at 06:50

How to detect if a mysql database column contains text or is empty

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