SnowConvert AI - SSIS¶

This section provides a comprehensive reference of SSIS elements and components that SnowConvert can convert to dbt and Snowflake. Control Flow elements (tasks and containers) become orchestration logic, while Data Flow components (sources, transformations, destinations) become dbt models.

Control Flow Elements¶

These SSIS Control Flow tasks and containers are supported:

Element

Category

Conversion Target

Notes

Microsoft.Pipeline (Data Flow Task)

Task

Complete dbt Project

-

Microsoft.ExecuteSQLTask

Task

Inline SQL or Stored Procedure

-

Microsoft.ExecutePackageTask

Task

Inline EXECUTE TASK or PROCEDURE call

-

Microsoft.SendMailTask

Task

SYSTEM$SEND_EMAIL with Notification Integration

Some features not supported; See Send Mail Task section

STOCK:SEQUENCE (Sequence Container)

Container

Inline sequential execution

-

STOCK:FORLOOP (For Loop Container)

Container

Sequential execution

Manual iteration logic required; Check EWI SSC-EWI-SSIS0004 for more information

STOCK:FOREACHLOOP (ForEach Loop Container)

Container

LIST/CURSOR pattern

Requires stage mapping; Check EWI SSC-EWI-SSIS0014 for more information

Event Handlers

Container

Not converted

Implement manually using Snowflake exception handling

Note: Unlisted Control Flow elements generate EWI SSC-EWI-SSIS0004.

Container Conversion Details¶

SSIS containers (Sequence, For Loop, ForEach, Event Handlers) are converted using an inline approach where container logic is expanded within the parent TASK or procedure rather than creating separate procedures.

Sequence Containers¶

Sequence containers are converted inline within the parent TASK. The container’s boundaries are marked with comments in the generated code, and all tasks within the container execute sequentially in the same TASK scope.

Conversion characteristics:

  • No separate procedure or TASK is created for the container

  • Container boundaries are clearly marked BEGIN … END blocks

  • All tasks execute sequentially within the parent TASK

  • Task execution order based on precedence constraints is maintained

  • Limitation: Only “Success” precedence constraints are fully supported. Conditional execution based on task outcomes (Failure or Completion constraints) is not currently implemented and will require manual post-migration adjustments

Behavioral differences:

  • FDM generated: SSC-FDM-SSIS0003

  • Variable scoping differs from SSIS: Container variables are accessible throughout the entire parent TASK, not just within the container scope

Example:

-- BEGIN Sequence Container: MySequence
-- Task 1 within sequence
EXECUTE DBT PROJECT public.DataFlow1 ARGS='build --target dev';
-- Task 2 within sequence  
EXECUTE DBT PROJECT public.DataFlow2 ARGS='build --target dev';
-- END Sequence Container: MySequence
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For Loop Containers¶

For Loop containers are converted to sequential execution of their contained tasks. However, the loop iteration logic itself requires manual implementation.

Conversion limitations:

  • The container executes once by default (iteration logic not automatically converted)

  • InitExpression, EvalExpression, and AssignExpression require manual conversion

  • An EWI (SSC-EWI-SSIS0004) is generated to indicate manual work is needed

Required manual steps:

  1. Review EvalExpression to understand the loop termination condition

  2. Implement the iteration using Snowflake’s WHILE loop construct

  3. Update AssignExpression logic for proper loop counter management

ForEach Loop Containers¶

File Enumerator (Supported)

ForEach File Enumerator containers are converted to Snowflake stage operations using the LIST command and cursor pattern:

-- List files from Snowflake stage
LIST @<STAGE_PLACEHOLDER>/FolderPath PATTERN = '.*/file_pattern\.csv';

-- Create cursor for iteration
LET file_cursor CURSOR FOR
   SELECT REGEXP_SUBSTR($1, '[^/]+$') AS FILE_VALUE
   FROM TABLE(RESULT_SCAN(LAST_QUERY_ID()))
   WHERE $1 NOT LIKE '%FolderPath/%/%';

-- Iterate through files
FOR file_row IN file_cursor DO
   User_CurrentFileName := :file_row.FILE_VALUE;
   EXECUTE DBT PROJECT public.My_DataFlow_Project ARGS='build --target dev';
END FOR;
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Configuration requirements:

After migration, you’ll need to:

  • Replace <STAGE_PLACEHOLDER> with your actual Snowflake stage name

  • Ensure the folder path is correctly mapped to a Snowflake stage

  • Verify that files are properly staged in Snowflake

An EWI (SSC-EWI-SSIS0014) is generated to remind you of this manual configuration step.

Other Enumerator Types

Other ForEach enumerator types (ForEach Item, ForEach ADO, ForEach NodeList, etc.) aren’t currently supported. SnowConvert generates an EWI (SSC-EWI-SSIS0004) for these cases. Consider implementing the equivalent logic using Snowflake queries or scripting constructs.

Event Handlers¶

Event handlers (OnError, OnWarning, OnPreExecute, OnPostExecute, etc.) aren’t supported. EWIs are generated. Implement manually using Snowflake exception handling.

Execute SQL Task¶

Execute SQL Tasks are converted as inline SQL statements or separate stored procedures, depending on complexity and result set bindings.

Conversion approach:

  • Simple SQL statements: Converted inline within the parent TASK

  • Complex statements with result sets: May be converted to separate stored procedures

  • Result bindings: Handled where possible; unsupported patterns generate EWI SSC-EWI-SSIS0011

Execute Package Task¶

Execute Package Tasks are handled differently based on package type:

Package Type

Conversion

Notes

Local (single reference)

Inline execution within parent TASK

Package logic expanded inline

Reusable (2+ references or parameters)

CALL to stored procedure

Enables synchronous execution with parameters; generates FDM SSC-FDM-SSIS0005

External

CALL with path resolution

Generates EWI SSC-EWI-SSIS0008 for manual verification

Asynchronous execution note:

TASK-based Execute Package conversions run asynchronously. For synchronous behavior, packages are converted to stored procedures. See EWI SSC-EWI-SSIS0005.

Send Mail Task¶

Send Mail Tasks are converted to Snowflake Tasks that use SYSTEM$SEND_EMAIL with a dynamically created Notification Integration.

Key Differences from SSIS¶

Aspect

SSIS

Snowflake

Email Service

Custom SMTP server

Snowflake’s built-in email service

Configuration

SMTP Connection Manager

Notification Integration

Sender Address

Custom FROM address

Fixed by Snowflake account

CC/BCC Support

Full support

Not supported (merged into recipients)

Attachments

File attachments supported

Not supported

HTML Body

Supported

Plain text only

Priority

High/Normal/Low

Not supported

Property Mapping¶

SSIS Property

Snowflake Equivalent

Notes

ToLine

ALLOWED_RECIPIENTS + recipients parameter

Direct mapping

FromLine

Prepended to message body

FDM SSC-FDM-SSIS0008

CCLine

Added to recipients list

FDM SSC-FDM-SSIS0009

BCCLine

Added to recipients list

FDM SSC-FDM-SSIS0010 (privacy concern)

Subject

subject parameter

Direct mapping

MessageSource

message parameter

Direct mapping

MessageSourceType (DirectInput)

Supported

-

MessageSourceType (Variable)

Supported

Variable reference converted

MessageSourceType (FileConnection)

Not supported

EWI SSC-EWI-SSIS0017

Priority

Not supported

EWI SSC-EWI-SSIS0016

FileAttachments

Not supported

EWI SSC-EWI-SSIS0015

SMTPConnection

Managed by Snowflake

FDM SSC-FDM-SSIS0007

BodyFormat (HTML)

Not supported

EWI SSC-EWI-SSIS0018

Conversion Output Structure¶

Each Send Mail Task is converted to a Snowflake Task containing:

  1. Notification Integration Creation: Created dynamically via EXECUTE IMMEDIATE

  2. SYSTEM$SEND_EMAIL Call: Sends the email through the integration

CREATE OR REPLACE TASK public.my_package_send_mail_task
WAREHOUSE=DUMMY_WAREHOUSE
AFTER public.my_package
AS
BEGIN
   -- Step 1: Create Notification Integration dynamically
   BEGIN
      LET my_package_Send_Mail_Task_integration_sql STRING := 'CREATE OR REPLACE NOTIFICATION INTEGRATION my_package_Send_Mail_Task
  TYPE=EMAIL
  ENABLED=TRUE
  ALLOWED_RECIPIENTS=("admin@example.com", "team@example.com")';
      EXECUTE IMMEDIATE :my_package_Send_Mail_Task_integration_sql;
   END;
   
   -- Step 2: Send the email
   CALL SYSTEM$SEND_EMAIL('my_package_Send_Mail_Task', 'admin@example.com,team@example.com', 'Subject', 'Message body');
END;
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Conversion Examples¶

Basic Email (To, Subject, Body):

BEGIN
   BEGIN
      LET my_package_Send_Mail_Task_integration_sql STRING := 'CREATE OR REPLACE NOTIFICATION INTEGRATION my_package_Send_Mail_Task
  TYPE=EMAIL
  ENABLED=TRUE
  ALLOWED_RECIPIENTS=("admin@example.com")';
      EXECUTE IMMEDIATE :my_package_Send_Mail_Task_integration_sql;
   END;
   CALL SYSTEM$SEND_EMAIL('my_package_Send_Mail_Task', 'admin@example.com', 'Daily Report', 'The daily report is ready.');
END;
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Email with FROM Address:

BEGIN
   BEGIN
      LET my_package_Send_Mail_Task_integration_sql STRING := 'CREATE OR REPLACE NOTIFICATION INTEGRATION my_package_Send_Mail_Task
  TYPE=EMAIL
  ENABLED=TRUE
  ALLOWED_RECIPIENTS=("noreply@company.com", "admin@example.com")';
      EXECUTE IMMEDIATE :my_package_Send_Mail_Task_integration_sql;
   END;
   --** SSC-FDM-SSIS0008 - SNOWFLAKE'S EMAIL INTEGRATION USES A FIXED SENDER ADDRESS. THE ORIGINAL FROM ADDRESS HAS BEEN PREPENDED TO THE MESSAGE BODY FOR REFERENCE. **
   CALL SYSTEM$SEND_EMAIL('my_package_Send_Mail_Task', 'noreply@company.com,admin@example.com', 'Notification', 'Email sent by: noreply@company.com

Package completed successfully.');
END;
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Email with Multiple Features (attachments, priority, CC):

BEGIN
   BEGIN
      LET my_package_Send_Mail_Task_integration_sql STRING := 'CREATE OR REPLACE NOTIFICATION INTEGRATION my_package_Send_Mail_Task
  TYPE=EMAIL
  ENABLED=TRUE
  ALLOWED_RECIPIENTS=("noreply@company.com", "admin@example.com", "team@example.com")';
      EXECUTE IMMEDIATE :my_package_Send_Mail_Task_integration_sql;
   END;
   !!!RESOLVE EWI!!! /*** SSC-EWI-SSIS0015 - SNOWFLAKE'S SYSTEM$SEND_EMAIL DOES NOT SUPPORT FILE ATTACHMENTS. CONSIDER USING STAGED FILES WITH SHARED LINKS OR ALTERNATIVE DELIVERY METHODS. ***/!!!
   !!!RESOLVE EWI!!! /*** SSC-EWI-SSIS0016 - EMAIL PRIORITY SETTINGS (HIGH/NORMAL/LOW) ARE NOT SUPPORTED BY SYSTEM$SEND_EMAIL AND WILL BE IGNORED. ***/!!!
   --** SSC-FDM-SSIS0008 - SNOWFLAKE'S EMAIL INTEGRATION USES A FIXED SENDER ADDRESS. THE ORIGINAL FROM ADDRESS HAS BEEN PREPENDED TO THE MESSAGE BODY FOR REFERENCE. **
   --** SSC-FDM-SSIS0009 - SNOWFLAKE'S SYSTEM$SEND_EMAIL DOES NOT SUPPORT CC ADDRESSING. ALL CC RECIPIENTS HAVE BEEN ADDED TO THE MAIN RECIPIENTS LIST. **
   CALL SYSTEM$SEND_EMAIL('my_package_Send_Mail_Task', 'noreply@company.com,admin@example.com,team@example.com', 'Monthly Report', 'Email sent by: noreply@company.com

Please review the attached monthly report.');
END;
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Prerequisites for Snowflake Email¶

Before using converted Send Mail Tasks:

  1. Email Notification Integration permissions: Account admin must grant CREATE INTEGRATION ON ACCOUNT to the executing role

  2. Recipient verification: All email addresses in ALLOWED_RECIPIENTS must be verified in Snowflake

  3. Update warehouse name: Replace DUMMY_WAREHOUSE with your actual warehouse name

Workarounds for Unsupported Features¶

File Attachments:

Upload files to a Snowflake stage and share links instead:

-- Upload file to stage
PUT file://report.pdf @my_stage;

-- Get shareable link (valid for 1 hour)
LET file_url STRING := GET_PRESIGNED_URL(@my_stage, 'report.pdf', 3600);

-- Include link in email body
CALL SYSTEM$SEND_EMAIL('my_integration', 'admin@example.com', 'Report Available', 
  'Download the report from: ' || :file_url);
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BCC Privacy:

Send separate emails to maintain recipient privacy:

-- Send to main recipients
CALL SYSTEM$SEND_EMAIL('my_integration', 'admin@example.com', 'Subject', 'Message');

-- Send separately to BCC recipients
CALL SYSTEM$SEND_EMAIL('my_integration', 'audit@example.com', 'Subject', 'Message');
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dbt Project Execution¶

Within the orchestration code, Data Flow Tasks are executed using Snowflake’s EXECUTE DBT PROJECT command:

EXECUTE DBT PROJECT schema.project_name ARGS='build --target dev'
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Important requirements:

  • The project_name must match the name you used when deploying the dbt project (via CREATE DBT PROJECT or Snowflake Workspace deployment)

  • Arguments passed are standard dbt CLI arguments (like build, run, test)

  • Each execution runs the entire dbt project with all models in dependency order

Deployment:

Before executing dbt projects in orchestration, deploy them using:

  • Snowflake CLI: snow dbt deploy --schema schema_name --database database_name --force package_name

  • Snowflake Workspace: Upload and deploy via UI

For complete deployment instructions, see the user guide.

Data Flow Components¶

These SSIS Data Flow sources, transformations, and destinations are supported:

Component

Category

dbt Mapping

Model Naming

Notes

Source Components

Microsoft.OLEDBSource

Source

Staging Model

stg_raw__{component_name}

-

Microsoft.FlatFileSource

Source

Staging Model

stg_raw__{component_name}

-

Transformation Components

Microsoft.DerivedColumn

Transformation

Intermediate Model (SELECT with expressions)

int_{component_name}

-

Microsoft.DataConvert

Transformation

Intermediate Model (CAST expressions)

int_{component_name}

-

Microsoft.Lookup

Transformation

Intermediate Model (LEFT JOIN)

int_{component_name}

Might present functional differences for ORDER BY requirements. Check FDM SSC-FDM-SSIS0001 for more information

Microsoft.UnionAll

Transformation

Intermediate Model (UNION ALL)

int_{component_name}

-

Microsoft.Merge

Transformation

Intermediate Model (UNION ALL)

int_{component_name}

Might present functional differences for sorted output. Check FDM SSC-FDM-SSIS0002 for more information

Microsoft.MergeJoin

Transformation

Intermediate Model (JOIN)

int_{component_name}

Might present functional differences for ORDER BY requirements. Check FDM SSC-FDM-SSIS0004 for more information

Microsoft.ConditionalSplit

Transformation

Intermediate Model (Router pattern with CTEs)

int_{component_name}

-

Microsoft.Multicast

Transformation

Intermediate Model (SELECT pass-through)

int_{component_name}

-

Microsoft.RowCount

Transformation

Intermediate Model with macro

int_{component_name}

Uses m_update_row_count_variable macro

Destination Components

Microsoft.OLEDBDestination

Destination

Mart Model (table)

{target_table_name}

-

Microsoft.FlatFileDestination

Destination

Mart Model (table)

{target_table_name}

-

Note: Unlisted Data Flow components generate EWI SSC-EWI-SSIS0001.