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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4fbfcbc1d3fc9bf6a117cf8ab1102db18602dfbdfe332b0d9d5f3d7564adbb0' 
  AND token = 'GTNRC+FbotOdKe+2MxzYtl2GTcOs6Z0nInCFt4tYRI4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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