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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef3b3f6c1435c570f63cc8685fc7040121d4f3bee9c029b5b641e87a38cf7451' 
  AND token = '4U4pWIHp48Lolis9wpvZNLZ7Ag4aTKZ8/1RgwG5yGLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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