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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd6f274343739d33791de89b4b75a9f1979a2c8a6516e3eadea8b1fa4d1c6f019' 
  AND token = 'ifjlmwxMPnIwJo2Uj0kxicVG2t/arKBSpfeEkq6Cgeg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}