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SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '113ea81918a5c5461c18b357e818e1b686fdd6cf56da9e66f4df89c98d152de6' 
  AND token = 'FjuchF+5IWGG7UAoV88U86GU8gFHpP19hlPJ4yPB34A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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