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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7e871c4a7886b51351ddaee480dd3f2528312991558faeb2b9fe02e66cc2c3a5' 
  AND token = 'qRGaP/pjh/qgo9Wk5EePX5vKtaqsfy+xDtcqf+xVwF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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