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SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'a5fcfb890ca7dd7c1e8b90f70df6f766e1491ab6d8ae599b5a6ba8faf01d55f4' 
  AND token = 'EvAFiLqtCkesF+fTmitDngPpM5QDolHImooRDbZJkF4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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