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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbce0d7de1df7d5e44c3f06fe5ee45f4de7b39211a68d8b390cf262d97566c7c' 
  AND token = 'MYWNPOSf5pvqR+8SdxKlH/HWd1yHgO6Mm9AEsVG3JJ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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