Data Conversion
transformation is used to convert the data type of a column. Same operation can
be done using “Derived Column “transformation using typecast but derived column
can also be used to add / create a new column by manipulating the existing
column based on expressions.
We have to
choose “Data Conversion” when the requirement is only intended to change the
data type. In other words “Data Conversion” is introduced just for developer
convenience as it’s a direct method where as in “Derived Column” we have to use
an expression to change the data type of a column.
From 2008 in
“Derived Column” transformation, data type and length information is read only,
when we create a new column or created from existing, data type would be
assigned based on the expression outcome and the data type is a read-only
column.
To change the
data type we have to use “Data Conversion” transformation.
