How to Bulk Insert Rows in Go

Go does not have a built-in 'bulk insert' function for databases; you must use your database driver's specific batch API or transaction support. For example, with the database/sql package and PostgreSQL, you typically use tx.Exec with a prepared statement inside a transaction to insert multiple rows efficiently.

import (
    "database/sql"
    _ "github.com/lib/pq"
)

func bulkInsert(db *sql.DB, rows []Row) error {
    tx, err := db.Begin()
    if err != nil {
        return err
    }
    defer tx.Rollback()

    stmt, err := tx.Prepare("INSERT INTO users (name, email) VALUES ($1, $2)")
    if err != nil {
        return err
    }
    defer stmt.Close()

    for _, r := range rows {
        if _, err := stmt.Exec(r.Name, r.Email); err != nil {
            return err
        }
    }
    return tx.Commit()
}

Note: For true bulk loading (e.g., 10k+ rows), use driver-specific features like pq.CopyIn for PostgreSQL or sqlx's Copy methods, as looping Exec is slow.

Bulk inserting means adding many rows to a database at once instead of one by one. In Go, you usually do this by opening a transaction and running a loop of insert commands, or by using a special "copy" command provided by your database driver. This is like mailing a whole stack of letters in one envelope rather than sending them individually.