Apa iku BSON lan tipe data apa wae sing MongoDB dukung?

Question

IT Interview Practice · Accepted Answer

**BSON** (Binary JSON) yaiku format biner sing MongoDB gunakake kanggo nyimpen dokumen — nglanjutake JSON karo tipe data tambahan (kaya tanggal, ObjectId, binary, lan tipe angka sing bener) lan efisien kanggo nyimpen lan nglalui. Mangerteni tipe BSON membantu kowe nyimpen data kanthi bener.

## BSON — binary JSON karo tipe-tipe luwih akeh

```text
JSON has limited types (string, number, boolean, null, object, array).
BSON adds: ObjectId, Date, Binary, Decimal128, distinct Int/Long/Double, Timestamp, etc.
→ BSON is more efficient (binary, typed, traversable) and richer than plain JSON text.
```

## Tipe data BSON umum

```js
{
  _id: ObjectId("..."),          // ObjectId — 12-byte unique id (the default _id type)
  name: "Ann",                    // String
  age: NumberInt(30),             // Int32 (32-bit integer)
  views: NumberLong(10000000000), // Int64 (64-bit — for large numbers)
  price: NumberDecimal("9.99"),   // Decimal128 — EXACT decimal (use for money!)
  rating: 4.5,                     // Double (default for numbers)
  active: true,                    // Boolean
  createdAt: ISODate("2024-01-15"),// Date (a proper date type, not a string)
  data: BinData(0, "..."),         // Binary data
  tags: ["a", "b"],                // Array
  address: { city: "NY" },          // Embedded document (object)
  deletedAt: null                   // Null
}
```

## ObjectId — _id sing default

```js
// ObjectId is a 12-byte id: timestamp + machine/process + counter → globally unique
// It even encodes a creation timestamp:
ObjectId("...").getTimestamp();   // get when the document was created
```

**ObjectId** (default `_id`) unik lan ngemot timestamp — dadi kurang luwih wis diurutake miturut wektu lan kowe entok wektu gawene kanthi gratis.

## Pertimbangan tipe penting

```text
✓ Use proper DATE type (ISODate), not date strings → enables date queries/sorting
✓ Use Decimal128 (NumberDecimal) for MONEY → exact (avoid Double's rounding errors)
✓ Be aware of Int32 vs Int64 vs Double — numbers default to Double; large ints need Long
✓ ObjectId vs custom _id — you can use your own _id, but ObjectId is convenient/unique
```

## Sebab penting

Mangerteni BSON lan tipe data MongoDB bisa dadi migunani kanggo **nyimpen data karo bener lan efisien**, dadi iku kawruh dasar sing migunani kanggo nganggo MongoDB.

Kabar yen MongoDB nggunakake **BSON** (binary JSON, luwih sugih lan luwih efisien tinimbang JSON murni) lan **tipe data sing didukung** mungguh JSON dasar — sing utama **tipe Date** sing bener, **ObjectId**, **Decimal128**, lan tipe integer/double sing beda — penting kanggo makili data kanthi akurat.

Saperangan pertimbangan tipe dadi penting kanthi praktis: nggunakake **tipe Date sing bener** (ISODate) tinimbang string tanggal (nglayani query tanggal lan sortir sing bener — kesalahan umum nyimpen tanggal dadi string), nggunakake **Decimal128 (NumberDecimal) kanggo dhuwit** (aritmetika desimal sing tepat, ngilangi kesalahan pembulatan Double — masalah koreksi kritis sing padha kaya ing SQL), lan aware marang pembedaan tipe angka (angka default menyang Double; angka besar kudu Int64/Long).

Mangerteni **ObjectId** (default `_id` — pengenal unik 12-byte sing gampang nyimpen timestamp gawean, dadi kurang luwih wis diurutake miturut wektu lan menehi wektu gawean kanthi gratis) iku migunani kanggo nganggo pengenal dokumen.

Sebab nyimpen data karo tipe sing bener mengarubi korektan (eksaktness dhuwit, fungsi tanggal), efisiensi, lan queryability, lan sebab sistem tipe BSON sing luwih sugih (khususan Date, Decimal128, lan ObjectId) yaiku cara MongoDB makili data kanthi akurat, mangerteni BSON lan tipe data MongoDB — tipe-tipe available, pertimbangan dhuwit/tanggal, lan ObjectId — yaiku kawruh migunani lan relevan kanthi praktis kanggo nrancang data MongoDB kanthi bener lan ngilangake kesalahan sing ana hubungane karo tipe umum (kaya tanggal string utawa dhuwit floating-point), aspek migunani saka nganggo database kanthi efektif.

BSON — binary JSON karo tipe-tipe luwih akeh

Tipe data BSON umum

ObjectId — _id sing default

Pertimbangan tipe penting

Sebab penting

Pitakon sing gegandhengan