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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52ae004893a9928d7c9046d1cc94fc324e8deb6c8bd76fa4d4e0d3dd7b7ba646' 
  AND token = 'd6ChQ5Yzy7NbiztWoskTwlpzotghDEi5C1VhHpMOYuw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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