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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d026e5e95ef3a0e7be7904f836a5e0128ead8653480cfa2a377e80bffd897a2' 
  AND token = 'qnYAGmZAY2fjNbFMCZ76LogX2QJ6pk5PnBaFlsUqs58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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