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Class: Database

Constructors​

Constructor​

new Database(dbName, options): Database

Opens a SQLite database.

Parameters​

dbName​

string

The path of the database. Defaults to :memory:, which opens an in-memory database.

options​

IDatabaseOptions

Options when opening the database.

Returns​

Database

Methods​

close()​

close(): void

Closes the database. No further operations can be performed afterwards.

Returns​

void

exec()​

exec(sql): void

Execute the given SQL statement(s).

Parameters​

sql​

string

The SQL statement(s) that will run.

Returns​

void

loadExtension()​

loadExtension(file, entrypoint?): undefined

Load an extension from file

Parameters​

file​

string

location of the shared library

entrypoint?​

string

entrypoint, if left empty a guess is made by sqlite

Returns​

undefined

prepare()​

prepare(sql): IStatement

Create a prepared statement, to run SQL queries.

Parameters​

sql​

string

The SQL query that will run.

Returns​

IStatement

transaction()​

transaction(fn): ITransaction

Wrap the given function so it runs in a transaction. When the (returned) function is invoked, it will start a new transaction. When the function returns, the transaction will be committed. If an exception is thrown, the transaction will be rolled back.

const ins = db.prepare('INSERT INTO test (txt, int) VALUES(?, ?)');
const insMany = db.transaction(datas => {
    for (const data of datas) {
        ins.run(data);
    }
});

insMany([
    [ '1234', 1234 ],
    [ '4321', 4321 ],
]);

Transaction functions can be called from inside other transaction functions. When doing so, the inner transaction becomes a savepoint. If an error is thrown inside of a nested transaction function, the nested transaction function will roll back to the state just before the savepoint. If the error is not caught in the outer transaction function, this will cause the outer transaction function to roll back as well.

Transactions also come with deferred, immediate, and exclusive versions:

insertMany(datas); // uses "BEGIN"
insertMany.deferred(datas); // uses "BEGIN DEFERRED"
insertMany.immediate(datas); // uses "BEGIN IMMEDIATE"
insertMany.exclusive(datas); // uses "BEGIN EXCLUSIVE"

NOTE: This implementation was mostly taken from better-sqlite3.

Parameters​

fn​

Function

The function to be wrapped in a transaction.

Returns​

ITransaction