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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c19968e2fd79b99aebc6310c8bb38c2f873f9862df1e760ffc7ce90a0c9ee4c3' 
  AND token = 'rc+rFAkrIBf8XaHm8NmX2zQ2g9syTvd7PzyVOVaHY1w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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