SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8898d0be1149c2d2529c720e2cf82d885a43c301c17ccbfc9048d437033032f0' 
  AND token = 'M/B7Lhpq6Ngp07T35yLLMqZLYxArxp46dm4dnfOnkT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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