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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '762d16d1e8874c72381fba0385b7978ed1f762ffd1a30d7e1c70c6c3b8e75c57' 
  AND token = 'qAZ4wRbIOp1GmkXLUo9tfDmSyfn1qHpZPYh1Wpg38Ds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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