* [Data Transformation](#data-transformation)

`postgres.js` comes with a number of built-in data transformation functions that can be used to transform the data returned from a query or when inserting data. They are available under `transformation` option in the `postgres()` function connection options.

Like - `postgres('connectionURL', { transformation: {...} })`

* `to`: The function to transform the outgoing query column name to, i.e ``SELECT ${ sql('aName') }` to `SELECT a_name` when using `postgres.toCamel`.

* `from`: The function to transform the incoming query result column name to, see example below.

> Both parameters are optional, if not provided, the default transformation function will be used.

Built in transformation functions are:

* For camelCase - `postgres.toCamel` and `postgres.fromCamel`

* For PascalCase - `postgres.toPascal` and `postgres.fromPascal`

* For Kebab-Case - `postgres.toKebab` and `postgres.fromKebab`

These functions can be passed in as options when calling `postgres()`. For example -

```js

(async function () {

const sql = postgres('connectionURL', { transform: { column: { to: postgres.fromCamel, from: postgres.toCamel } }});

await sql`CREATE TABLE IF NOT EXISTS camel_case (a_test INTEGER, b_test TEXT)`;

await sql`INSERT INTO camel_case ${ sql([{ aTest: 1, bTest: 1 }]) }`

const data = await sql`SELECT ${ sql('aTest', 'bTest') } FROM camel_case`;

console.log(data) // [ { aTest: 1, bTest: '1' } ]

process.exit(1)

})();

> Note that if a column name is originally registered as snake_case in the database then to tranform it from camelCase to snake_case when querying or inserting, the column camelCase name must be put in `sql('columnName')` as it's done in the above example.