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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '343617ae7d73cbd79746a53d1d067765eaecf5bae76126de320cd070c8f56717' 
  AND token = '7ypcRLNRJ1zgi8fM0x7SVlQbVBNqo424nHzYrhmP0Qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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