Approach

This is possible. The main difficulty is the variable nature of the string lengths, which will typically cause the output data to be difficult to read.

To address this, I suggest that you:

• Find the maximum string length in each column
• Output Headers with top and lower borders, with header names padded to be same width as maximum cell width
• Output each row with the cells padded to the target column width.

Code Sample

I'm not able to unit-test the code shown below at present, but it should be ok; post a comment if you have any trouble.

<?php

// Open connection
$mysqli = new mysqli("db_host", "db_user", "db_password", "db_schema");

// Check that connection succeeded
if ($mysqli->connect_errno) {
    printf("Connect failed: %s\n", $mysqli->connect_error);
    exit();
}

// Prepare query
$query = "SELECT * FROM `myTable`";

// Fetch results as associative array
$resultSet = [];
if ($result = $mysqli->query($query)) {

    while ($row = $result->fetch_assoc()) {
        $resultSet[] = $row;
    }

    // Free result set
    $result->free();

    // Close Connection to DB
    $mysqli->close();
} else {

  // Close Connection to DB and print error message
  $mysqli->close();
  die('An error occurred when executing SQL, please check your SQL query.');
}



// If results empty, output error
if (count($resultSet)<1) {
  die('<pre>----NO DATA----'+"\n\n"+'Please revise your query</pre>');
}

// Get column names
$keys = array_keys($resultSet[0]);

// Iterate over column names, get starting widths
$maxLength = [];
foreach ($keys as $column) {
  $maxLength[$column] = mb_strlen($column);
}

// Iterate over result-set, get maximum string length for each column
foreach ($resultSet as $row) {
  foreach ($keys as $column) {

    // If current cell length is greater than column width, increase column width
    if (mb_strlen($row[$column]) > $maxLength[$column]) {
      $maxLength[$column] = mb_strlen($row[$column]);
    }

  }
}

echo '<pre>';

// Output top border
echo '+';
foreach ($keys as $column) {
  echo str_repeat('-', $maxLength[$column]+2);
  echo '+';
}
echo "\n";

// Output header
echo '| ';
foreach ($keys as $column) {
  echo $column.str_repeat(' ', $maxLength[$column] - mb_strlen($column));
  echo ' | ';
}
echo "\n";

// Output bottom border
echo '+';
foreach ($keys as $column) {
  echo str_repeat('-', $maxLength[$column]+2);
  echo '+';
}
echo "\n";

// Output all rows
foreach ($resultSet as $row) {
  echo '| ';
  foreach ($keys as $column) {
    echo $row[$column].str_repeat(' ', $maxLength[$column] - mb_strlen($row[$column]));
    echo ' | ';
  }
echo "\n";
}

echo '</pre>';


?>

NOTE The above code is multi-byte safe but it disregards character width; if the output contains characters of variable width then there might be slight 'kinks' in the column separators. This may be worth a revision if you encounter such problems in the display.