SELECT ?
SELECT ?
SELECT ?..
SELECT ?.., 
SELECT ?.., 
SELECT ?..
SELECT ?.. WHERE ?
SELECT ?.. WHERE ? = ?
SELECT ?.. WHERE ? = ? AND (x, y)
SELECT ?.. WHERE ? = ? AND (?, y)
[?..]
[?.., x]
SELECT ?.. WHERE ? = ? AND (?, y) LIMIT ?..
SELECT ? AS `xyz`
SELECT ? AS `xyz1`
SELECT ? AS `xyz11`
SELECT ? AS `?`
SELECT ? AS xyz1
SELECT ? AS xyz11
SELECT ? xyz11
SELECT ?, xyz11
SELECT ?..
SELECT ? xyz11
SELECT ?, xyz11
SELECT ?..