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  1. Preface
  2. Introduction to Informatica Big Data Management
  3. Connections
  4. Mappings in the Hadoop Environment
  5. Mapping Objects in the Hadoop Environment
  6. Processing Hierarchical Data on the Spark Engine
  7. Stateful Computing on the Spark Engine
  8. Monitoring Mappings in the Hadoop Environment
  9. Mappings in the Native Environment
  10. Profiles
  11. Native Environment Optimization
  12. Data Type Reference
  13. Complex File Data Object Properties
  14. Function Reference
  15. Parameter Reference

LAG

LAG

The LAG function returns data from preceding rows.
LAG uses the following syntax:
LAG ( Column name, Offset, Default )
LAG returns the value at an offset number of rows before the current row. Use the LAG function to compare values in the current row with values in a previous row. Use the following arguments with the LAG function:
  • Column name. The column name whose value from the prior row is to be returned.
  • Offset. The number of rows preceding the current row from which the data is to be retrieved. For example, an offset of "1" accesses the previous row, and an offset of "3" accesses the row that is three rows before the current row.
  • Default. The default value to be returned if the offset is outside the scope of the partition. If you do not specify a default, the default is NULL.
For more information about the LAG function, see the
Informatica Transformation Language Reference
.


Updated November 09, 2018