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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8400849f43fe9d8b9080d24deaf28419d76a937da5ea4c3cf63a8e812aa29682' 
  AND token = 'bA4jt1IOkuJ7LylY8DzM7nzjRB9DLZ7730wCpUNRpK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}