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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b49dbc4fb97ce3ca9b856f9e79fdfcda73b26f92577a3e2cd9b44b516f0d9191' 
  AND token = 'QOz93vPhb1PSDkHS/E4MPtc0UP521JyD9LWex7h5Jw8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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