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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'fa0aa80620f8441ee3ed938998ff035e81555c69e292b471e00f7e01bb1bd30d' 
  AND token = 'qKUVe4MI/gZbZfoFQVDv40Vq3jKR2SkI3zOsMTitgEE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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