Component mapping

Every SSIS task, container and data flow component the importer has a converter for, the Apache Hop action or transforms it becomes, and how the migration report classifies it. The report names components by their SSIS class (Microsoft.DerivedColumn, STOCK:FOREACHLOOP, …), shown here next to each.

Status is what the converter reports when it carries the component across:

• Automatic: a converter carries the component's settings across. Automatic is a statement about what the importer did, not a guarantee that the result behaves identically.
• Partial: converted, but a known part of the behaviour is not; the component is always flagged for review.

What conversion actually did can change this per component in the report: a setting the converter cannot carry (an error output, a parameter mapped to a variable that does not exist, a file name computed by an expression, …) flags the component as Partial with the reason, and a part that needs a person makes it Manual. A component or task whose converter fails becomes a placeholder and is reported Unsupported. Components not listed here have no converter: they become a Dummy placeholder that keeps their name, position and hops, and are reported Unsupported.

Control flow

SSIS	Class	Hop	Status	Notes
Package	Microsoft.Package	Workflow	Automatic	Package variables and parameters become workflow parameters; variables computed by expressions are evaluated when the workflow starts
Sequence container	STOCK:SEQUENCE	Workflow, run by a Workflow action	Automatic
For Loop container	STOCK:FORLOOP	Repeat action around an iteration: check the condition, run the body, assign	Automatic
Foreach Loop container	STOCK:FOREACHLOOP	A pipeline that lists the items and runs the loop body per item with a Workflow executor	Automatic	File, item (fixed list) and ADO (rows of a query) enumerators; other enumerators are placeholders
Data Flow Task	Microsoft.Pipeline	Pipeline action	Automatic	One pipeline per Data Flow Task
Execute SQL Task	Microsoft.ExecuteSQLTask	SQL action	Automatic	? parameters bound to variables become ${variables}, in quotes for string and date variables, and are flagged; stored procedure return values and output parameters are not converted
Execute SQL Task, single-row result	Microsoft.ExecuteSQLTask	A pipeline: Table input, then Set variables	Automatic
Execute SQL Task, statement from an expression	Microsoft.ExecuteSQLTask	A pipeline that computes the statement and runs it (Execute row SQL script)	Automatic
Execute T-SQL Statement Task	Microsoft.DbMaintenanceTSQLExecuteTask	SQL action	Automatic
Execute Package Task, project reference	Microsoft.ExecutePackageTask	Workflow action, with the parameter bindings	Automatic
Execute Package Task, file reference	Microsoft.ExecutePackageTask	Workflow action on the converted package	Partial	Runs the converted package if it was imported with the project
Expression Task	Microsoft.ExpressionTask	A pipeline that evaluates the expression and sets the variable	Automatic
File System Task	Microsoft.FileSystemTask	Copy files, Delete file, Create folder	Automatic	Copy, move and rename file or directory, delete file, create directory; directory deletes are placeholders
Send Mail Task	Microsoft.SendMailTask	Mail action	Automatic
Execute Process Task	Microsoft.ExecuteProcess	Shell action	Automatic
Script Task	Microsoft.ScriptTask	Dummy placeholder	Manual	Its C# or Visual Basic is written next to the workflow, as .cs.txt or .vb.txt
Disabled task or container		Dummy, treated as succeeded	Automatic

Precedence constraints and event handlers

SSIS	Hop	Status	Notes
Success, failure and completion constraints	Hops that follow success, failure, or unconditionally	Automatic	Tasks that do not depend on each other run in parallel, as in SSIS. Several tasks one task waits for run in a workflow of their own; a Join action is used only for other shapes, and flagged
Constraint with an expression	The expression is evaluated and checked by a Simple evaluation; when false, the branch ends without error	Automatic
OnPreExecute, OnPostExecute, OnError handlers	The package or task runs in a workflow between its handlers, in SSIS's order; on failure OnError and OnPostExecute, then Abort	Partial on a package or container	A package's or container's OnPreExecute and OnPostExecute run once, not for every task inside; OnError runs once, without System::ErrorDescription
OnWarning, OnInformation and other handlers	Not converted	Manual	Hop has no such events
System variables (System::StartTime, System::PackageName, …)	Variables System.StartTime, …, set by a pipeline when the package starts	Automatic	Start time, execution GUID, machine, user, and the package's name, id and version

Data flow

SSIS	Class	Hop	Status	Notes
OLE DB Source, ADO.NET Source, ODBC Source	Microsoft.OLEDBSource, Microsoft.DataReaderSourceAdapter, Microsoft.SSISODBCSrc	Table input	Automatic	A table becomes a SELECT of the selected columns; ? parameters become ${variables}, and are flagged
OLE DB, ADO.NET, SQL Server and ODBC Destination	Microsoft.OLEDBDestination, Microsoft.ADONETDestination, Microsoft.SQLServerDestination, Microsoft.SSISODBCDst	Table output, with the column mapping	Automatic	After an OLE DB Command or a Slowly Changing Dimension, a Blocking transform first collects the whole input, so the row updates finish before the inserts start, as with SSIS's buffers
Flat File Source, delimited	Microsoft.FlatFileSource	CSV file input, then If null for empty values	Automatic	SSIS reads an empty value as an empty string or zero; date and time columns are read as strings, and flagged
Flat File Source, fixed width or ragged right	Microsoft.FlatFileSource	Text file input of type Fixed, one row per line	Automatic
Flat File Destination	Microsoft.FlatFileDestination	Text file output; padded columns for fixed width	Automatic
Excel Source	Microsoft.ExcelSource	Microsoft Excel input	Automatic
Excel Destination	Microsoft.ExcelDestination	Microsoft Excel writer	Partial	Check the header row of a new workbook
Derived Column	Microsoft.DerivedColumn	User Defined Java Class with the translated expressions	Automatic
Conditional Split	Microsoft.ConditionalSplit	User Defined Java Class that picks the output, then Switch / case	Automatic	A condition that evaluates to NULL fails, as in SSIS
Lookup, full cache	Microsoft.Lookup	Table input + Stream lookup + Filter rows for the match and no-match outputs	Automatic	Exact match, as SSIS compares in .NET; the first reference row of a key wins; Abort where SSIS fails on no match
Lookup, partial or no cache	Microsoft.Lookup	Database join with SSIS's own per-row query	Automatic	The database's collation decides what matches, as in SSIS
Lookup on a cache connection	Microsoft.Lookup	De-serialize from file (the cache file), then as any Lookup	Automatic
Cache Transform	Microsoft.Cache	Select values + Serialize to file	Partial	The cache becomes a file in ${java.io.tmpdir}/hop-ssis-cache
Fuzzy Lookup	Microsoft.FuzzyLookup	Table input (reference table) + Fuzzy match by pair-letter similarity	Partial	Several join columns are joined into one key; scores differ from SSIS's
Data Conversion	Microsoft.DataConvert	Calculator, copy of field with the target type	Automatic	A User Defined Java Class with SSIS's casts for date, time and binary columns
Sort	Microsoft.Sort	Sort rows; unique rows when duplicates are removed	Automatic
Merge Join	Microsoft.MergeJoin	Merge join + Select values for the output columns	Automatic	Flagged after a Sort with comparison flags (such as ignore case): SSIS's Merge Join ignores them, so its result depends on row order
Union All	Microsoft.UnionAll	Select values per input (+ Add constants for unmapped columns) into a Dummy	Automatic
Merge	Microsoft.Merge	Select values per input into a Sorted merge	Automatic
Multicast	Microsoft.Multicast	Dummy that copies rows to every hop	Automatic
Aggregate	Microsoft.Aggregate	Memory group by	Automatic
Row Count	Microsoft.RowCount	The rows pass on; a copy is counted and the count set in the variable	Automatic
Audit	Microsoft.Lineage	Get variables, from the system variables	Automatic
Percentage Sampling	Microsoft.PctSampling	User Defined Java Class that draws each row + Filter rows to the selected and unselected outputs	Automatic
Row Sampling	Microsoft.RowSampling	Reservoir sampling	Automatic	Only when the unselected output is not used; otherwise a placeholder
Character Map	Microsoft.CharacterMap	User Defined Java Class	Automatic	Lowercase and uppercase, in place or into a new column; other mappings are placeholders
Unpivot	Microsoft.UnPivot	Row normaliser + Select values + Filter rows that drops NULL values, as SSIS does	Automatic
OLE DB Command	Microsoft.OLEDBCommand	Execute SQL script, per row, with bound parameters	Automatic	Parameters bind in the command's order
Slowly Changing Dimension	Microsoft.SCD	Table input of the current dimension rows + Unique rows + Stream lookup + User Defined Java Class that picks the outputs + Switch / case (and Filter rows for the historical output)	Automatic	Business keys compare without case and trailing spaces, unless SSIS_KEYS_IGNORE_CASE is N; the wizard's downstream flow converts as it is
Script Component	Microsoft.ScriptComponentHost	Dummy placeholder; with --translate-scripts, a User Defined Java Class	Manual; Partial when translated	Its code is written next to the pipeline, with a .script.json of its columns; see Translate Script Components
Error outputs		Hop error handling on the rejecting transform	Automatic	Where a converter does not route them, the component is flagged

Expressions

SSIS expressions are parsed and translated into Java, which runs in User Defined Java Classes with a small runtime that keeps SSIS's rules: NULL propagates, && and || use three-valued logic, ?: and the logic operators evaluate lazily, casts such as (DT_WSTR, 50) and (DT_NUMERIC, 10, 2) convert as SSIS does, and the string, math, date and NULL functions behave like SSIS's (1-based SUBSTRING, FINDSTRING, TOKEN, DATEADD, DATEDIFF counting boundaries, …). Two choices are the importer's: a cast of a number with a fraction to an integer rounds half away from zero, and a cast to a string of a given length cuts a longer value. An expression the translator does not support leaves the component a placeholder, with the expression in the report.

Not converted

These become placeholders and are listed in the report with the settings to redo: Fuzzy Grouping, Term Extraction, Term Lookup, Pivot, Data Profiling, XML, Web Service, Analysis Services and CDC tasks and components, and third-party components.