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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e1a5fb504f0275155df7c273662519b09e67a49510925d7739d444269acee509' 
  AND token = '+YRomyfqjZhyCkWkmuZYS5QEHYE2uvploIVg3CiONak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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