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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff14b9eee62f6aef0f1bddc2b9b3f9a64b0dca6cb1e7f710f9e5d829213e1308' 
  AND token = 'c6nqnv1MsHtOV38nVdn5T5Eci3MRVKe3BLg2fdy6UQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}