SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ba9812fcef24e7745e545c43b379c57cabfb3a0c64464a17b92946f6cf05c0e' 
  AND token = 'RyKhUfXsTgw067+JDas+I9kGNV7pMHqHW23ANUSwVT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}