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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fd0791706069242d586cd0cec689b4d0dff9075c59630e85b4ffd64c8d5f573d' 
  AND token = 'Qj6KfDu9cICSoDhESJZkV1fx5wVdVk9cb5zL+rxnK/Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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