db Connection not able to display table on webpage

db Connection not able to display table on webpage

How to display a table from database(mysql) on webpage (PHP) i am not able
to display..
$con=mysqli_connect("localhost", "ABC", "PW","DBN");
if (mysqli_connect_errno($con))
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
DONE Connection now what to write??
Query:
( SELECT "username" AS SourceTable, username FROM user_info WHERE id =
'$u_id' ) UNION ( SELECT "exam1" AS SourceTable,score FROM exam1 WHERE id
= '$u_id' ) UNION ( SELECT "exam2" AS SourceTable,score FROM exam2 WHERE
id = '$u_id' ) UNION ( SELECT "exam3" AS SourceTable,score FROM exam3
WHERE id = '$u_id' ) UNION ( SELECT "exam4" AS SourceTable,score FROM
exam4 WHERE id = '$u_id' ) UNION ( SELECT "exam5" AS SourceTable,score
FROM exam5 WHERE id = '$u_id' ) UNION ( SELECT "exam6" AS
SourceTable,score FROM exam6 WHERE id = '$u_id' ) UNION ( SELECT "exam7"
AS SourceTable,score FROM exam7 WHERE id = '$u_id' ) UNION ( SELECT
"exam8" AS SourceTable,score FROM exam8 WHERE id = '$u_id' ) UNION (
SELECT "exam9" AS SourceTable,score FROM exam9 WHERE id = '$u_id' ) UNION
( SELECT "exam10" AS SourceTable,score FROM exam10 WHERE id = '$u_id' )
UNION ( SELECT "exam11" AS SourceTable,score FROM exam11 WHERE id =
'$u_id' ) UNION ( SELECT "exam12" AS SourceTable,score FROM exam12 WHERE
id = '$u_id' ) UNION ( SELECT "exam13" AS SourceTable,score FROM exam13
WHERE id = '$u_id' ) UNION ( SELECT "exam14" AS SourceTable,score FROM
exam14 WHERE id = '$u_id' ) UNION ( SELECT "exam15" AS SourceTable,score
FROM exam15 WHERE id = '$u_id' ) UNION ( SELECT "exam16" AS
SourceTable,score FROM exam16 WHERE id = '$u_id' ) UNION ( SELECT "exam17"
AS SourceTable,score FROM exam17 WHERE id = '$u_id' ) UNION ( SELECT
"exam18" AS SourceTable,score FROM exam18 WHERE id = '$u_id' ) UNION (
SELECT "exam19" AS SourceTable,score FROM exam19 WHERE id = '$u_id' )
UNION ( SELECT "exam20" AS SourceTable,score FROM exam20 WHERE id =
'$u_id' )
How to display a table from database(mysql) on webpage (PHP) i am not able
to display..