Liquid Studio Documentation
Data Mapping / Data Mapper Functions / By Category / Date Time / Day
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    Function Name
    Retrieve the day portion of a DateTime value
    DateTime DateTime value to retrieve day from
    Day Day value from DateTime input
    None -


    The Data Mapper DateTime Day function returns the day portion of a DateTime value. Many applications use DateTime values to record information about events, for example retail or other account transactions. It is often necessary to retrieve particular portions of a DateTime value, such as the day, or to separate the DateTime into its component parts for the target application. To apply the DateTime Day function, use the following process:

    Create a new Data Mapper file, dragging your XML data source and targets into the editor area. For this example we are using sales_source.xsd, an XML Schema Definition inferred from the following source:

    Source XML
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    For our target schema we will be using sales_alt_target.xsd, inferred from the following XML:

    Target XML
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     <sale id="8987612312" item="y6yt5i93e4">
     <sale id="2090176549" item="i8u7b45f7y">
     <sale id="2819283722" item="y6yt5i93e4">

    The data models retail transactions, including the DateTime for when a sale was made. Let's assume that in this case we want to map the day and month during which each transaction took place, perhaps for marketing purposes. We will therefore need to retrieve both the day and month values from the input DateTime value, mapping these two to separate elements in the target. Here is the Data Mapper with Source and Target imported:

    Data Mapper Source and Target

    Drag the DateTime Day function from the Component Palette into the mapping area:

    Day Component

    Day Transform Added

    The Day function takes a single input, the DateTime in question, giving an output comprising the day portion. The input should be connected to the source item, which will normally be an item in the XML Reader. The output should be connected to the target item, whether an item in the XML Writer or another component in the Mapper, for example if you plan on using the Day value to sort or filter the data in terms of purchases made throughout the months in a year.

    Connect the Day function input to the "transaction" output in the XML Reader and the Day output to the "day" input in the XML Writer.

    Day Mapped

    Let's now map the month value as well. Drag a Month component from the DateTime section onto the Mapper. Connect it also to the "transaction" output in the XML Reader and to the "month" input in the XML Writer.

    Month Mapped

    Now the Mapper will retrieve two values from each DateTime input in the source data. Each transaction will include elements for both the day and the month.

    Finally, connect the remaining inputs and outputs:

    Input and Output Connections Mapped

    We can now execute the transform by pressing Shift-F5 or the Execute button (Execute). The transform is applied and the file we selected as output opens in the editor:

    Output XML
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     <sale id="9099879823" item="ab65gh7hh7">
     <sale id="2390865748" item="g7hy65tfd3">
     <sale id="8250987123" item="d4rf54r0op">

    The output contains indicators of the days and months during which each transaction was made, with day represented as a number between 1 and 31.

    If you pass a value to the Day function that is not a DateTime, the Mapper will attempt to parse it. If you pass the Day function a DateTime value which does not contain a day portion, the function will output a value of 1 by default.

    This is a scalar function so the standard rules apply if multiple values are presented to one or more inputs.

    See Also