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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d89793c66424066fc534baafa4c73142174d42e15dee8486b9c057c62346503' 
  AND token = '++IzN5UyFb5D9kiQuUAVW3l+Y/NlrzWu+43S+XQZJoM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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