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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b399b0b1ecb2817617d35cf7ce5b22a45cff5ed0c27430e6bf2bf0c36160b5c9' 
  AND token = 'LNO2hKiNPtCtkbpjCRs971DymziLmZ/6b9uAOy5aIws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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