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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe38bbc7ad7c613b05be30a15967203a761b98c9e06d9e410b3aa8b7387b6aaa' 
  AND token = 'yj5f2I80IXH2Ohltxa4l11bhqIoh+8UBT2CqS2ZFQSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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