To split data you need to set the Splitter XPath on the source hierarchy. The data is split and sent to the transformer which executes the split data. You can set the Splitter XPath in case of a single source schema only. You can also set multiple Splitter XPaths in a source schema.
The following example explains the use of multiple Xpath splitting:
In this scenario we have Root element as the Root for schema. It has two child elements R1 and R2 at the first level. R1 element has two children R1C1 andR1C2. R2 element has two children R2C1 and R2C2.
If in the source xml, there are multiple occurrences for R1 and R2 elements, then we need to set split XPath on both R1 and R2 elements. If we set split XPath on R1 element only then the Data Mapper will assume that R2 has only one occurrence and vice versa. Similarly, if child elements R1C1, R1C2, R2C1 andR2C2 have multiple occurrences, then also R1 and R2 should be set as split XPath. Thus the thumb rule is that the top most node which is repeating, should be set as splitter XPath.
Once splitter XPath is defined, during execution, mapping will split the source hierarchy using each splitter Xpath and each chunk will have records specified by Split Number of Records.
In this scenario, when we set R1 and R2 as split XPath then Split Number of Records property is applied for both R1 and R2. For example if the value of Split Number of Records property is 500 then 500 records of R1 and 500 records of R2 are selected.
Splitting data and setting Splitter XPath is very effective when the source data is very large. You can set the Splitter XPath in case of a single source and target schema. You can also set multiple Splitter XPaths in a source and target schema.
It is advised to always split the file and set the Splitter XPath if the file size is greater than 30 MB. This enhances the performance and increases data reliability, as in some cases such execution of large data can fail and generate errors.
Steps to set Splitter XPath
- Ensure that all the source and target schemas are loaded and all their elements are listed under their respective nodes.
Right-click the source schema element that you want to split and select the Set as Splitter XPath option. A screen showing the Splitter XPath details is displayed (see Figure 466).
Figure 466: Splitter XPath Details
Splitting can be set only on root or record levels. You cannot split on an element level.
Click OK. This splits and sets the Splitter XPath on the selected source element.
Once a Splitter XPath is set for a source element, the letter (S) is displayed next to that source element. This signifies that the source element has been split and the Splitter XPath has been set. Refer to Table of Table of Suffixes for details on suffixes displayed next to an element.
Once you have set a Splitter XPath, you can view it in the Output XML.