SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74ba35e7294ef55eea528d4cef9b8969826527bc799548db9e256976b17fc591' 
  AND token = 'v9z0EsrVhxmg7e0ihq83olO6hIiOr6pGXcw2vZnAoNk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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