Funnel Stage

What is Funnel Stage in Data Stage?

The Funnel stage is an active stage used to combine multiple input data streams into a single output stream.

 It appends rows vertically (row-wise combination), not column-wise.

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1️. Basic Funnel Stage Diagram

Input 1 (File / Table A)

   |

   v

          +-----------+

Input 2 ->|  FUNNEL   |----> Single Output

          +-----------+

   ^

   |

Input 3

Explanation

·        Multiple input links

·        One output link

·        All rows are combined into one flow

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2️. Funnel Stage Row-Wise Example

Input Data

Input 1

ID  NAME

1   A

2   B

Input 2

ID  NAME

3   C

4   D

Funnel Output :

ID  NAME

1   A

2   B

3   C

4   D

 Rows are appended, not joined

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3️.Funnel Stage in Parallel Processing

              Input Links

        -------------------------

        |           |           |

      In1          In2          In3

        |           |           |

     +------+    +------+    +------+

     |FUNNEL|    |FUNNEL|    |FUNNEL|

     +------+    +------+    +------+

        |           |           |

        -------------------------

                   |

             Single Output

Explanation

• Funnel works in parallel
• Each input contributes rows
• Output is one combined stream

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4️. Funnel vs Join .

FUNNEL (Append Rows)

-------------------

Input1: 1 A

Input2: 1 B

Output : 1 A  1 B

JOIN (Combine Columns)

---------------------

Input1: 1 A

Input2: 1 B

Output : 1 A B

✔ Funnel = UNION ALL
✔ Join = JOIN

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5️.Funnel vs Union Stage

Multiple Inputs

      |

      v

FUNNEL STAGE   (Older, flexible)

UNION STAGE    (Newer, simpler)

Funnel		Union
Available in older versions		Introduced later
Supports many inputs		Cleaner design
Schema must match		Schema must match

  Functionally similar

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6️. Common Funnel Use Case (Real-Time)

Scenario: Combine Daily Files

File_A

   |

File_B ----> FUNNEL ----> Target Table

   |

File_C

✔ All records loaded into one target

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7️.Funnel with Reject Link

Input 1

   |

Input 2 ---> FUNNEL ---> Output

   |

Input 3

            |

            v

         Reject

✔ Rejects rows with schema issues

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8️.Funnel vs Sort vs Merge :

FUNNEL → Appends rows

SORT   → Orders rows

MERGE  → Combines sorted streams

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All input links must have IDENTICAL metadata, including:

• Column names

• Column order

• Data types (int, varchar, decimal, date, etc.)

• Length / precision / scale

• Nullability

• Key position (if defined)

If any one input link’s metadata changes, the Funnel stage fails at compile time (or sometimes at runtime).