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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5a1cf8eecb172544b8b9fd5a4e303cc75ee8aa35e0283fdfb0617310196d5e5c' 
  AND token = 'kbn4HzcLoGwKPGwIz2i8AthSOMrEHvxR0zBEHR4XMxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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