Filtering in flex AdvancedDataGrid using input text

I have a advancedDatagrid with column headers having input text开发者_运维技巧 boxes for filtering.The column is filtered according to input text when I use characters as data inside that column.But when I use numbers in the column field,filtering does not happen.Can anyone tell me what went wrong.

Any help would be appreciated.

TIA

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I think you are from Mahindra city.