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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b912c84b43fe01ed2e0f0f0a5a1a8811d8fb7b65bc8399ec3cbc1d97fe71051' 
  AND token = '5t3eKqj3//WFeCWRgfveWFfrT9xq6eS53eEP8UJjLE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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