# xSQL Schema Definition

> The xSQL configuration file can be used to define a database schema.

> ### For an overview see page Configuration File Parameters

> The database schema can be defined either by quoting the schema definition in a text string or by specifying a schema file.

> ## Schema File

> The database schema can be loaded from an external file that defines that database using eXtremeDB DDL. For example, the following configuration file entry would load the schema definition from file `schema.mco`:

>         schema_file : "schema.mco",

> ## Inline Schema Definition

> The database schema can also be defined by an inline text string that expresses the eXtremeDB DDL . For example:

>         schema :
>         "
>         #define uint2     unsigned<2>
>         declare database  locatedb;
>         class Employee
>         {
>             string name;
>             uint2 dept_no;

>             unique tree<name> Iname;
>             tree<dept_no>     Idept;
>         };
>         ",