table = Document.Data.Tables[jsonParam['tableName']]
column = None
for testedColumn in table.Columns:
    if(testedColumn.Name == jsonParam['name']):
        column = testedColumn.As[CalculatedColumn]()
        if(column == None):
            table.Columns.Remove(jsonParam['name'])
        break
if(column == None):
    column = table.Columns.AddCalculatedColumn(jsonParam['name'],jsonParam['expression']).As[CalculatedColumn]()
else:
    column.Expression = jsonParam['expression']
if(jsonParam['isFrozen']):
    column.Freeze()

