ST
Transaction Set Header .
Pos: 010 Max: 1
Heading - Mandatory
Loop: N/A Elements: 2
.

To indicate the start of a transaction set and to assign a control number Element Summary:

                     
  _Ref_ Id _________Element Name__________ Req Type Min/Max ___Usage___  
  ST01 143 Transaction Set Identifier Code M ID 3/3 Must use  
      Description: Code uniquely identifying a Transaction Set
        Code Name_______________________________
      850 Purchase Order
  ST02 329 Transaction Set Control Number M AN 4/9 Must use  
      Description: Identifying control number that must be unique within the transaction set functional group assigned by the originator for a transaction set
      I/C Note : The number is sequentially assigned by the sender. The number must be unique within the functional group.

Semantics:
1. The transaction set identifier (ST01) used by the translation routines of the interchange partners to select the appropriate transaction set definition (e.g., 810 selects the Invoice Transaction Set).

Example:
ST*850*0001~

Transaction Set
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