I have a SELECT statement which is successfully populating the data I need within the following table. However I want to filter down the results with an if statement. Basically I want to have it where:

If there is a value for Timestamp and/or msg get results else leave blank.

<?php foreach ( $result as $query ){ ?>
    <tr>
        <td><?php echo $query->text1; ?></td>
        <td><?php echo $query->text2; ?></td>
        <td><?php echo $query->text3; ?></td>
        <td><?php if($query->Timestamp!=""){echo date('m/d/y', strtotime($query->Timestamp)); }?></td>
        <td><?php echo $query->msg; ?></td>
    </tr>
<?php }?>

How would I write this if statement into this code in order to only show rows that produced either a date or a msg or both?

As requested I have added the initial query though a bit intricate hence I was hoping to avoid messing with it any further.

$result = $wpdb->get_results(
    "SELECT DISTINCT text3,
        CASE WHEN text3 LIKE '%S' THEN S_Msg
             WHEN text3 LIKE '%N' THEN N_Msg
             ELSE E_Msg
             END AS msg,
        CASE WHEN text3 LIKE '%S' THEN S_Time
             WHEN text3 LIKE '%N' THEN N_time
             WHEN text3 LIKE '%E' THEN E_time
             END AS Timestamp,
        value1
        FROM table_1 AS a
        INNER JOIN table_2 AS b
            ON a.Value2 = b.Value3
        WHERE value1='$value1'");

I am open to suggestions for either solution that works :)

UPDATE

I have tried using the suggestion made by M Khalid Junaid

 having (msg is not null and msg <> '')
 or (Timestamp is not null and Timestamp <> '')

however this causes issues with other queries no longer loading as I think due to me not using groups but multiple different queries on the page and this is just one of them within a bigger set of queries.

I fear this one is over my head. to replicate this on a sqlfiddle i would need to setup 3 database tables so will need a day to prepare that unless someone has another solution. I am still open to the cop out of a if statement as well lol

You can add an AND statement at the end that checks Timestamp or N_msg as not being empty

$result = $wpdb->get_results(
"SELECT DISTINCT text3,
    CASE WHEN text3 like '%S' THEN S_Msg
         WHEN text3 like '%N' THEN N_Msg
         ELSE E_Msg
         END AS msg,
    CASE WHEN text3 LIKE '%S' THEN S_Time
         WHEN text3 LIKE '%N' THEN N_time
         WHEN text3 LIKE '%E' THEN E_time
         END AS Timestamp,
    value1
    FROM table_1 AS a
    INNER JOIN table_2 AS b
        ON a.Value2 = b.Value3
    WHERE value1='$value1'
    AND N_msg != '' OR S_time != '' OR N_time != '' OR E_time != ''");

To get the results if any criteria is met you can use following

select  distinct text3,
        case when text3 like '%S' then S_Msg when text3 like '%N' then N_Msg else E_Msg end as msg,
        case when text3 like '%S' then S_Time when text3 like '%N' then N_time when text3 like '%E' then E_time end as Timestamp,
        value1 
from table_1 as a 
inner join table_2 as b on a.Value2 = b.Value3 
where value1='$value1'
having (msg is not null and msg <> '')
or (Timestamp is not null and Timestamp <> '')

Not sure about how your data is saved in DB as NULL or with empty so i added both filters. Purpose to use having clause is to apply filter on custom aliases

You could probably do it like this - using the alias in a having clause

select distinct 
    text3, 
    case 
        when text3 like '%S' then S_Msg 
        when text3 like '%N' then N_Msg 
        else E_Msg 
    end as msg,
    case 
        when text3 like '%S' then S_Time 
        when text3 like '%N' then N_time 
        when text3 like '%E' then E_time 
    end as Timestamp, 
    value1 
    from table_1 as a 
    inner join table_2 as b on a.Value2 = b.Value3 
    having value1='$value1' and msg is not null and timestamp is not null