Some minor things that when dealing with conversion from Excel to SAS sometimes aren't minor.
4.when i exported to sas it shows as mm/dd/yy format as numeric 8.
EXCEL and SAS both use numeric values for date, time or datetime values. The way tell that such values are intended to be used as such is shown by applying a date, time or datetime format. The underlying numeric values do not change but the format may.
Depending on the particular method used to convert data between Excel and SAS, SAS may attempt to duplicate the display appearance of the dates. If you right click on a cell populated with one of these date values in EXCEL you should see a cell format box pop up that will indicate what role the cell plays such as General, Number, Currancy, Date and a few others. If the cell is a date then that role will be selected and another part of the window should show the current display format in effect though Excel will provide an example appearance (generally) to select. SAS format descriptions use letters such as DD to indicate the day of month position, MM the month position and YY the year position in a date. Some of the behavior of the order of those fields can depend on your national language so it is not impossible to see a value in Excel appear differently in SAS because the numeric value in Excel could be displayed in day moth year order and get transposed to a month day year order if that is the national preference set in SAS (or vice versa).
On not uncommon behavior is for an Excel sheet to have columns that mix numeric values with date display formats and character values of similar appearance if people are entering or modifying data manually. At which point you have have missing values or character date values, again depending on how you convert the data.
Using SAS you do want to get some terminology a bit clearer when using the word "format" as that is a very specific meaning. A variable with have a format and the name is important and would be reported by clicking on displayed tabled headings or running Proc Contents on a data set or even using one of the information functions. Your SAS data set displays a value like mm/dd/yy but that is not a format as the format name is not allowed to have special characters. The FORMAT might be MMDDYY10. to show 10 characters, default using a / between the elements which would be displayed with 2 digits for month and day and 4 digits for the year. It is a good idea to specify the exact format SAS uses for a variable as some "problems" may well be addressed by changing formats such as displaying more or fewer characters, different or no delimiter between date or time elements and even which elements to display. SAS supplies over 50 date related formats and you can create custom appearances for dates using Proc Format if one of the existing formats doesn't fit your need.
... View more