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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed9d0ebf1ee87c54b639e97ee3ffb11937f0b8b39b3fafa9ff427bc3b2e9f376' 
  AND token = 'ZfrcKzmMt5Lz1isEIiM1rW8FIX6aOA1Gpit+rf4v6TE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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