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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'b14a218175b5a4313bce78a096671aada0a6683685d61a308c871fa8cdc70b28' 
  AND token = 'oUjsqBMDgYIR4f9rPGt7kvIT081wgDLeUltw2J8ceIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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