The DATASOURCE Procedure
- Overview
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Getting Started
Structure of a SAS Data Set Containing Time Series DataReading Data FilesSubsetting Input Data FilesControlling the Frequency of Data – The INTERVAL= OptionSelecting Time Series Variables – The KEEP and DROP StatementsControlling the Time Range of Data – The RANGE StatementReading in Data Files Containing Cross SectionsObtaining Descriptive Information on Cross SectionsSubsetting a Data File Containing Cross SectionsRenaming Time Series VariablesChanging the Lengths of Numeric Variables -
Syntax
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Details
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ExamplesBEA National Income and Product AccountsBLS Consumer Price Index SurveysBLS State and Area Employment, Hours, and Earnings SurveysDRI/McGraw-Hill Format CITIBASE FilesDRI Data Delivery Service DatabasePC Format CITIBASE DatabaseQuarterly COMPUSTAT Data FilesAnnual COMPUSTAT Data Files, V9.2 New Filetype CSAUC3CRSP Daily NYSE/AMEX Combined Stocks
- References
KEEP Statement
KEEP variable-list ;
The KEEP statement specifies which variables in the data file are to be included in the OUT= data set. Only the time series and event variables can be specified in a KEEP statement. All the BY variables and the time ID variable DATE are always included in the OUT= data set; they cannot be referenced in a KEEP statement. If they are referenced, a warning message is given and the reference is ignored.
The variable list can contain variable names or name range specifications. See Variable Lists for details.
There is a default KEEP list for each file type. Usually, descriptor type variables, like footnotes, are not included in the default KEEP list. If you give a KEEP statement, the default list becomes undefined.
Only one KEEP or one DROP statement can be used. KEEP and DROP are mutually exclusive.
You can also use the KEEP= data set option to control which variables to include in the OUT= data set. However, the KEEP statement differs from the KEEP= data set option in several respects:
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The KEEP statement selection is applied before variables are read from the data file, while the KEEP= data set option selection is applied after variables are read and as they are written to the OUT= data set. Therefore, using the KEEP statement instead of the KEEP= data set option is much more efficient.
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If the KEEP statement causes no series variables to be selected, then no observations are output to the OUT= data set.
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The KEEP statement variable specifications are applied to each cross section independently. This behavior may produce variables different from those produced by the KEEP= data set option when order-range variable list specifications are used.