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better-sqlite3-multiple-cip…/docs/integer.md
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2018-09-25 03:22:40 -04:00

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# The `Integer` class
SQLite3 can store data in 64-bit signed integers, which are too big for JavaScript's [number format](https://en.wikipedia.org/wiki/Double-precision_floating-point_format) to fully represent. To support this data type, `better-sqlite3` uses the immutable `Integer` class. To view the complete `Integer` documentation, [click here](https://github.com/JoshuaWise/integer).
```js
const { Integer } = require('better-sqlite3');
const integer = Integer('95073701505997');
integer.toString(); // returns "95073701505997"
integer.toNumber(); // returns 95073701505997
const bigInteger = Integer('1152735103331642317');
bigInteger.toString(); // returns "1152735103331642317"
bigInteger.toNumber(); // throws a RangeError, cannot be represented in JavaScript
```
## Binding Integers
`Integers` can bind to [`Statements`](./api.md#class-statement) just like regular numbers. You can also return `Integers` from [user-defined functions](./api.md#functionname-options-function---this).
```js
db.prepare("SELECT * FROM users WHERE id=?").get(Integer('1152735103331642317'));
db.prepare("INSERT INTO users (id) VALUES (?)").run(Integer('1152735103331642317'));
```
## Getting Integers from the database
By default, integers returned from the database (including the [`info.lastInsertRowid`](./api.md#runbindparameters---object) property) are normal JavaScript numbers. You can change this default as you please:
```js
db.defaultSafeIntegers(); // Integers by default
db.defaultSafeIntegers(true); // Integers by default
db.defaultSafeIntegers(false); // JavaScript numbers by default
```
Additionally, you can override the default for individual [`Statements`](./api.md#class-statement) like so:
```js
const stmt = db.prepare(SQL);
stmt.safeIntegers(); // Safe integers ON
stmt.safeIntegers(true); // Safe integers ON
stmt.safeIntegers(false); // Safe integers OFF
```
[User-defined functions](./api.md#functionname-options-function---this) can receive `Integers` as arguments. You can override the database's default setting like so:
```js
db.function('isInt', { safeIntegers: true }, (value) => {
return String(value instanceof Integer);
});
db.prepare('SELECT isInt(?)').pluck().get('foobar'); // => "false"
db.prepare('SELECT isInt(?)').pluck().get(Integer.MAX_VALUE); // => "true"
```
It's worth noting that REAL (FLOAT) values returned from the database will always be represented as JavaScript numbers.