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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb0b46f4fe6b0cef8e0eb1fd1aedb5bddac1fe1668aaa5e15275e9308b0c5e23' 
  AND token = 'zxEur35HlONlHYiaEnjvMxE4b3GcehBCt3DzNEHwptY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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