help xmlsave, help xmluse dialogs: xmlsave xmluse
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Title
[D] xmlsave -- Save and use datasets in XML format
Syntax
Save data in memory to XML-format dataset
xmlsave filename [if] [in] [, xmlsave_options]
Save subset of data in memory to XML-format dataset
xmlsave varlist using filename [if] [in] [, xmlsave_options]
Use XML-format dataset
xmluse filename [, xmluse_options]
xmlsave_options description
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Main
doctype(dta) save XML file by using Stata's .dta
format
doctype(excel) save XML file by using Excel XML format
dtd include Stata DTD in XML file
legible format XML to be more legible
replace overwrite existing filename
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xmluse_options description
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doctype(dta) load XML file by using Stata's .dta
format
doctype(excel) load XML file by using Excel XML format
sheet("sheetname") Excel worksheet to load
cells(upper-left:lower-right) Excel cell range to load
datestring import Excel dates as strings
allstring import all Excel data as strings
firstrow treat first row of Excel data as
variable names
missing treat inconsistent Excel types as
missing
nocompress do not compress Excel data
clear replace data in memory
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Menu
xmlsave
File > Export > XML data
xmluse
File > Import > XML data
Description
xmlsave and xmluse allow datasets to be saved or used in XML file formats
for Stata's .dta and Microsoft Excel's SpreadsheetML format. XML files
are advantageous because they are structured text files that are highly
portable between applications that understand XML.
xmlsave saves the data in memory in the dta XML format by default. To
save the data, type
. xmlsave filename
although sometimes you will want to explicitly specify which document
type definition (DTD) to use by typing
. xmlsave filename, doctype(dta)
xmluse can read either an Excel-format XML or a Stata-format XML file
into Stata. You type
. xmluse filename
Stata will read into memory the XML file filename.xml, containing the
data after determining whether the file is of document type dta or excel.
As with the xmlsave command, the document type can also be explicitly
specified with the doctype() option.
. xmluse filename, doctype(dta)
It never hurts to specify the document type; it is actually recommended
because there is no guarantee that Stata will be able to determine the
document type from the content of the XML file. Whenever the doctype()
option is omitted, a note will be displayed that identifies the document
type Stata used to load the dataset.
If filename is specified without an extension, .xml is assumed.
Options for xmlsave
+------+
----+ Main +-------------------------------------------------------------
doctype(dta|excel) specifies the document type definition (DTD) to use
when saving the dataset.
doctype(dta), the default, specifies that an XML file will be saved
using Stata's .dta format (see [P] file formats .dta). This is
analogous to Stata's binary dta format for datasets. All data that
can normally be represented in a normal dta file will be represented
by this doctype.
doctype(excel) specifies that an XML file will be saved using
Microsoft's SpreadsheetML document type definition. SpreadsheetML is
the term given by Microsoft to the Excel XML format. Specifying this
document type produces a generic spreadsheet with variable names as
the first row, followed by data. It can be imported by any version
of Microsoft Excel that supports Microsoft's SpreadsheetML format.
dtd when combined with doctype(dta) embeds the necessary document type
definition into the XML file so that a validating parser of another
application can verify the dta XML format. This option is rarely
used, however, because it increases file size with information that
is purely optional.
legible adds indents and other optional formatting to the XML file making
it more legible for a person to read. This extra formatting,
however, is unnecessary and in larger datasets can significantly
increase the file size.
replace permits xmlsave to overwrite existing filename.xml.
Options for xmluse
doctype(dta|excel) specifies the document type definition (DTD) to use
when loading data from filename.xml. Although optional, use of
doctype() is encouraged. If this option is omitted with xmluse, the
document type of filename.xml will be determined automatically. When
this occurs, a note will display the document type used to translate
filename.xml. This automatic determination of document type is not
guaranteed, and the use of this option is encouraged to prevent
ambiguity between various XML formats. Specifying the document type
explicitly also improves speed, as the data are only passed over once
to load, instead of twice to determine the document type. In larger
datasets, this advantage can be noticeable.
doctype(dta) specifies that an XML file will be loaded using Stata's
dta format. This document type follows closely Stata's binary .dta
format (see [P] file formats .dta).
doctype(excel), specifies that an XML file will be loaded using
Microsoft's SpreadsheetML document type definition. SpreadsheetML is
the term given by Microsoft to the Excel XML format.
sheet("sheetname") imports the worksheet named sheetname. Excel files can
contain multiple worksheets within one document, so using the sheet()
option specifies which of these to load. The default is to import
the first worksheet to occur within filename.xml.
cells(upper-left:lower-right) specifies a cell range within an Excel
worksheet to load. The default range is the entire range of the
worksheet, even if portions are empty. Often times the use of
cells() is necessary because data are offset within a spreadsheet, or
only some of the data need to be loaded. Cell range notation follows
the letter-for-column and number-for-row convention that is popular
within all spreadsheet applications. The following are valid
examples:
. xmluse filename, doctype(excel) cells(A1:D100)
. xmluse filename, doctype(excel) cells(C23:AA100)
datestring forces all Excel SpreadsheetML date formats to be imported as
strings to retain time information that would otherwise be lost if
automatically converted to Stata's date format. With this option,
time information can be parsed from the string after loading it.
allstring forces Stata to import all Excel SpreadsheetML data as string
data. Although data type information is dictated by SpreadsheetML,
there are no constraints to keep types consistent within columns.
When such inconsistent use of data types occurs in SpreadsheetML, the
only way to resolve inconsistencies is to import data as string data.
firstrow specifies that the first row of data in an Excel worksheet
consist of variable names. The default behavior is to generate
generic names. If any name is not a valid Stata variable name, a
generic name will be substituted in its place.
missing forces any inconsistent data types within SpreadsheetML columns
to be imported as missing data. This can be necessary for various
reasons but often will occur when a formula for a particular cell
results in an error, thus inserting a cell of type ERROR into a
column that was predominantly of a NUMERIC type.
nocompress specifies that data not be compressed after loading from an
Excel SpreadsheetML file. Because data type information in
SpreadsheetML can be ambiguous, Stata initially imports with broad
data types and, after all data are loaded, performs a compress to
reduce data types to a more appropriate size. The following table
shows the data type conversion used before compression and the data
types that would result from using nocompress:
SpreadsheetML type Initial Stata type
-------------------------------------------
String str244
Number double
Boolean double
DateTime double
Error str244
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clear clears data in memory before loading from filename.xml.
Examples saving XML files
To save the current Stata dataset to a file, auto.xml type
. xmlsave auto
To overwrite an existing XML dataset with a new file containing the
variables make, mpg, and weight, type
. xmlsave make mpg weight using auto, replace
To save the dataset to an XML file for use with Microsoft Excel, type
. xmlsave auto, doctype(excel) replace
Examples using XML files
Assuming that we have a file named auto.xml that was saved using the
doctype(dta) option of xmlsave, we can read in this dataset with the
command
. xmluse auto, doctype(dta) clear
If the file was saved from Microsoft Excel to a file called auto.xml that
contained the worksheet Rollover Data, with the first row representing
column headers (or variable names), we could import the worksheet by
typing
. xmluse auto, doctype(excel) sheet("Rollover Data") firstrow clear
Continuing with the previous example, if we wanted just the first column
of data in that worksheet, and we knew there were only 75 rows, including
one for the variable name, we could have typed
. xmluse auto, doc(excel) sheet("Rollover Data") cells(A1:A75) first
clear
Also see
Manual: [D] xmlsave
Help: [D] compress, [D] fdasave, [D] infiling, [D] odbc, [D] outfile,
[D] outsheet, [D] save
