(V45) Trigger Execution Sequence in Forms 4.5

本文详细介绍了 Oracle Forms 4.5 中各种触发器的执行顺序,包括运行表单、查询、执行查询、退出、字段操作、记录操作、块操作等场景下的触发器顺序。

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(V45) Trigger Execution Sequence in Forms 4.5
=============================================

Introduction



This document lists the order in which triggers fire in Oracle Forms 4.5:
  o The first column, Action, describes the function to be performed
     (e.g. deleting a record).
  o The second column, Trigger Firing Order, describes the order
     in which triggers fire after a function is performed.
  o The third column, Level, describes the level (form, block, item)
     at which the trigger fires. This was accomplished by creating a form
     with all the triggers invoked. If a trigger could fire at all levels,
     it was included at all levels. Such a trigger fires at the lowest level
     at which it is defined.

Key triggers and triggers which fire via buttons or check boxes are
not included.

This bulletin does not cover every contingency and covers only the
most commonly used actions.

Action Trigger Firing Order Level



Runform 1. Pre-Logon Form
                         2. On-Logon Form
                         3. Post-Logon Form
                         4. Pre-Form Form
                         5. When-Create-Record Block
                         6. Pre-Block Block
                         7. Pre-Record Block
                         8. Pre-Text-Item Item
                         9. When-New-Form-Instance Form
                         10. When-New-Block-Instance Block
                         11. When-New-Record-Instance Block
                         12. When-New-Item-Instance Item

***********
Enter Query 1. Post-Text-Item Item
                         2. Post-Record Block
                         3. When-Clear-Block Block
                         4. When-New-Record-Instance Block
                         5. When-New-Item-Instance Item

Note: If you define the Key-ENTQRY trigger, this is the only trigger
       which fires in an Enter Query situation.

*****************
Execute Query
After Enter Query 1. Pre-Query Block
2. Pre-Select Block
3. On-Select Block
4. When-Clear-Block Block
5. Post-Select Block
6. On-Fetch Block
7. On-Close Form
8. When-Clear-Block Block

Note: If you define the Key-EXEQRY trigger, this is the only trigger
which fires in an Execute Query situation.

*************
Execute Query
Without Enter
Query 1. Post-Text-Item Block
2. Pre-Query Block
3. Pre-Select Block
4. On-Select Block
5. Post-Select Block
6. On-Fetch Block
7. On-Close Form
8. When_Create_Record Block
9. Pre-Record Block
10. Pre-Text-Item Item
11. When-New-Record-Instance Block
12. When-New-Item-Instance Item

****
Exit 1. Post-Text-Item Item
2. Post-Record Block
3. Post-Block Block
4. Post-Form Form
5. On-Rollback Form
6. Pre-Logout Form
7. On-Logout Form
8. Post-Logout Form

**************
Next Field and
Previous field 1. When-New-Item-Instance Item

***************
Next Record and
Previous Record 1. When-New-Record-Instance Block
2. When-New-Item-Instance Item

**************
Next Block and
Previous Block 1. Post-Text-Item Item
2. Post-Record Block
3. Post-Block Block
4. When-Create-Record Block
5. Pre-Block Block
6. Pre-Record Block
7. Pre-Text-Item Block
8. When-New-Block-Instance Block
9. When-New-Record-Instance Block
10. When-New-Item-Instance Form

*******************
Records Are Queried 1. Post-Query Block
2. Post-Change Block
3. Post-Change Item
4. Post-Change Block
5. Post-Change Block
Go back to Post-Query

NOTE: This cycle is repeated for each record retrieved.

**********************
No Records Are Queried 1. When-New-Record-Instance Block
2. When-New-Item-Instance Item

NOTE: To observe this Trigger Firing Order:
a. Enter a query.
b. Enter a nonexistent record.
c. Execute the query.

The two triggers listed above, the Enter Query triggers, and
the Execute Query triggers fire.

*************
Create Record 1. Post-Change Block
2. When-Validate-Item Block
3. Post-Text-Item Block
4. When-Validate-Record Block
5. Post-Record Block
6. Post-Block Block
7. On-Savepoint Form
8. Pre-Commit Form
9. Pre-Insert Block
10. On-Insert Form
11. Post-Insert Block
12. Post-Forms-Commit Form
13. On-Commit Form
14. Post-Database-Commit Form
15. Pre-Block Block
16. Pre-Record Block
17. Pre-Text-Item Block
18. When-New-Item-Instance Form

*************
Update Record 1. When-Database-Record Block
2. Post-Change Block
3. When-Validate-Item Block
4. Post-Text-Item Block
5. When-Validate-Record Block
6. Post-Record Block
7. Post-Block Block
8. On-Savepoint Form
9. Pre-Commit Form
10. Pre-Update Block
11. On-Update Block
12. Post-Update Block
13. Post-Forms-Commit Form
14. On-Commit Form

Here the transaction is complete and one record added.

15. Post-Database-Commit Form
16. Pre-Text-Item Block
17. When-New-Item-Instance Form

NOTE: To observe this Trigger Firing Order:

a. Execute a query.
b. Change a value.
c. Choose Action->Save from the menu.
d. Record the triggers from that point.

*************
Delete Record 1. On-Lock Block
2. When-Remove-Record Block
3. Post-Change Block
4. Post-Change Block
5. Post-Change Block
6. Post-Change Block
7. Post-Change Block
8. Post-Change Block
9. Post-Change Item
10. Post-Query Block
11. Post-Text-Item Block
12. Post-Record Block
13. Pre-Record Block
14. Pre-Text-Item Block
15. When-New-Record-Instance Block
16. When-New-Item-Instance Form

NOTE: To observe this Trigger Firing Order, delete a detail record.

Related Topic:http://blog.youkuaiyun.com/pan_tian/article/details/7978903

source:https://forums.oracle.com/forums/thread.jspa?threadID=431216

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