SQLIteStore LEFT JOIN and add new fields to select

[wwwjsx]

Hi !

this my store:

this.store = new Ext.data.SQLiteStore ({
            dbFile      : 'data/unitech.db',
            tableName   : Unitech.Tables.Product,
            baseParams  : { start: 0, limit: this.pageSize },
            idProperty  : 'id',
            autoLoad    : true,
            remoteSort  : true,
            sortInfo    : { field: 'date_added', direction: 'DESC' },
            fields      : [
                { type: 'int',      name: 'id' },
                { type: 'string',   name: 'barcode' },
                { type: 'string',   name: 'name' },
                { type: 'int',      name: 'category_id' },
                { type: 'float',    name: 'price' },
                { type: 'int',      name: 'unit' },
                { type: 'int',      name: 'date_added' },
                { type: 'int',      name: 'date_modified'  },
                { type: 'int',      name: 'total' },
                { type: 'int',      name: 'available' }
            ],
        }); 

How can I add LEFT JOIN and new columns to SQL.

Thanks