SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e177192f157faea54ea2ec1189bec742afe8ace531795ea27b2aaec87602ccc' 
  AND token = 'NLSVBKRhVeDnWYpj0RkHjBszLMcX2EPlq7j0IBi/0hE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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