Saving Buffer on Postgres bytea with TypeORM only store 10 bytes

When you want to save a 10-byte buffer using TypeORM in a PostgreSQL database, first determine the appropriate data type for the field in your database model. In PostgreSQL, you can typically use the bytea type to store byte data.

The following example demonstrates how to define a model and save an entity with a bytea field in TypeORM.

Assume we have an entity named FileData that contains a field data of type bytea to store byte data.

First, define the entity model:

typescript
import { Entity, PrimaryGeneratedColumn, Column } from "typeorm";

@Entity()
export class FileData {

    @PrimaryGeneratedColumn()
    id: number;

    @Column("bytea")
    data: Buffer;
}

In this model, the @Column("bytea") decorator specifies that the data field should store byte data.

Next, here's how to insert and save a 10-byte buffer into the FileData table:

typescript
import { createConnection } from "typeorm";
import { FileData } from "./FileData";

async function saveData() {
    const connection = await createConnection(/* fill in your database connection configuration here */);
    const fileDataRepository = connection.getRepository(FileData);

    // Create a new FileData entity
    const fileData = new FileData();
    fileData.data = Buffer.from([0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0A]);

    // Save the entity to the database
    await fileDataRepository.save(fileData);

    console.log("Data saved");
    await connection.close();
}

saveData().catch(console.error);

In this example, we create a new FileData instance and set the data field to a 10-byte Buffer. We then use TypeORM's save() method to persist the entity to the database.

This approach ensures correct storage of byte data in PostgreSQL. It is applicable not only for 10-byte data but also for larger or smaller byte arrays.