SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d371412625760c8cd327c813fb2e8495c30d4e7c611cecddf537f6754d01dac' 
  AND token = 'P+8mIpsmsFjYMgziLb0nvNdahGoValLCZE4DH31WmzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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