Kepiye ngganti mapping nganggo reindex lan alias?

Question

IT Interview Practice · Accepted Answer

Alias iku jeneng ajeg sing nuduhake index. Yen field butuh owah-owahan mapping sing ora kompatibel, gawe index anyar banjur pindhah jeneng kasebut sawise mriksa data salinan.

## Gambarake owah-owahane

```text
Before: application -> products -> products-v1
After:  application -> products -> products-v2
```

Aplikasi tetep nganggo `products`. Gawe dhisik `products-v2` kanthi mapping lan setelan sing dikarepake. Reindex nyalin document, nanging ora otomatis nyalin konfigurasi index sumber.

## Gunakake migrasi prasaja yen tulisan bisa dijeda

- Jedakake tulisan aplikasi, kalebu panulis latar mburi, nalika maca tetep kasedhiya yen cocog.
- Reindex v1 menyang v2, priksa kegagalan, banjur priksa document lan kueri perwakilan sawise data salinan bisa digoleki.
- Ganti alias, tes maca lan nulis aplikasi, banjur terusake panulis.

Kanggo alias sing saiki mung nuduhake v1, panjaluk Kibana Dev Tools iki ngalih nganggo siji update alias:

```http
POST /_aliases
{
  "actions": [
    {"remove":{"index":"products-v1","alias":"products","must_exist":true}},
    {"add":{"index":"products-v2","alias":"products","is_write_index":true}}
  ]
}
```

Priksa respons sadurunge nerusake tulisan. Iki nyingkiri sela remove/add kapisah; ora nyalin owah-owahan sing kliwatan nalika migrasi.

## Yen tulisan ora bisa dijeda

Sampeyan butuh cathetan awet saka owah-owahan sajrone nyalin lan cara muter maneh update lan delete tanpa data lawas nimpa data anyar. Iki desain sinkronisasi dhewe. Simpen v1 sementara, nanging aja nganggep mbalekake menyang v1 tanpa kelangan data sawise tulisan anyar tekan v2.

[Dokumentasi resmi](https://www.elastic.co/docs/manage-data/data-store/aliases).

Gambarake owah-owahane

Gunakake migrasi prasaja yen tulisan bisa dijeda

Yen tulisan ora bisa dijeda

Pitakon sing gegandhengan