# db

{% hint style="warning" %}
Before using this module, make sure to install `unixodbc`:

* Windows - Install `Windows SDK`
* OS X - `brew install unixodbc`
* Linux - `sudo apt-get install unixodbc unixodbc-dev` or `sudo dnf install unixODBC unixODBC-devel`
  {% endhint %}

## callProcedure

Calls a stored procedure.

\*\* Usage example:\*\*

```javascript
// calls a procedure which expects two input parameters and one output parameter.
var result = db.callProcedure('test', 3, 4, undefined);
log.info(result);
```

**Parameters:**

| Name   | Type        | Description                                                                                                                |
| ------ | ----------- | -------------------------------------------------------------------------------------------------------------------------- |
| `name` | `String`    | Name of the procedure to call.                                                                                             |
| `args` | `...Object` | `optional` Procedure arguments. If procedure produces output parameters then these need to be specified using `undefined`. |

**Returns:**

`Object` - Procedure output if any.

## executeNonQuery

Executes SQL statement.

Any results from the query are discarded.

**Parameters:**

| Name    | Type     | Description           |
| ------- | -------- | --------------------- |
| `query` | `String` | The query to execute. |

## executeQuery

Executes SQL query and returns the result set.

**Parameters:**

| Name    | Type     | Description           |
| ------- | -------- | --------------------- |
| `query` | `String` | The query to execute. |

**Returns:**

`Object` - The result set.

## getScalar

Executes SQL query and returns the first column of the first row in the result set.

**Parameters:**

| Name    | Type     | Description           |
| ------- | -------- | --------------------- |
| `query` | `String` | The query to execute. |

**Returns:**

`Object` - The first column of the first row in the result set, or null if the result set is empty.

## setConnectionString

Sets DB connection string to be used by other methods.

This method doesn't actually open the connection as it's opened/closed automatically by query methods.\
Example connection strings:\
\- `Driver={MySQL ODBC 9.0 Unicode Driver};Server=localhost;Database=myDatabase; User=myUsername;Password=myPassword;Option=3;`\
\- `Driver={Oracle in instantclient_11_2};dbq=127.0.0.1:1521/XE;uid=myUsername; pwd=myPassword;`

**Parameters:**

| Name         | Type     | Description             |
| ------------ | -------- | ----------------------- |
| `connString` | `String` | ODBC connection string. |