Click here to view and discuss this page in DocCommentXchange. In the future, you will be sent there automatically.

SQL Anywhere 10.0.1 » MobiLink - Server Administration » Synchronization Events

report_odbc_error connection event Next Page

resolve_conflict table event


Defines a process for resolving a conflict in a specific table.

Parameters

In the following table, the description provides the SQL data type. If you are writing your script in Java or .NET, you should use the appropriate corresponding data type. See SQL-Java data types and SQL-.NET data types.

In SQL scripts, you can specify event parameters by name or with a question mark, but you cannot mix names and question marks within a script. If you use question marks, the parameters must be in the order shown below and are optional only if no subsequent parameters are specified (for example, you must use parameter 1 if you want to use parameter 2). If you use named parameters, you can specify any subset of the parameters in any order.

Parameter name for SQL scripts

Description

Order

s.remote_id VARCHAR(128). The MobiLink remote ID. You can only reference the remote ID if you are using named parameters.Not applicable

s.username

VARCHAR(128). The MobiLink user name.

1

s.table

VARCHAR(128). The table name.

2

Default action

None.

Remarks

When a row is updated on a remote database, the MobiLink client saves a copy of the original values. The client sends both old and new values to the MobiLink server.

When the MobiLink server receives an updated row, it compares the original values with the present values in the consolidated database. The comparison is carried out using the upload_fetch script.

If the old uploaded values do not match the current values in the consolidated database, the row conflicts. Instead of updating the row, the MobiLink server inserts both old and new values into the consolidated database. The old and new rows are handled using the upload_old_row_insert and upload_new_row_insert scripts, respectively. If you are using cursor-based uploads the rows are handled using old_row_cursor and new_row_cursor, respectively.

Once the values have been inserted, the MobiLink server executes the resolve_conflict script. It provides the opportunity to resolve the conflict. You can implement any scheme of your choosing.

This script is executed once per conflict.

Alternatively, instead of defining the resolve_conflict script, you can resolve conflicts in a set-oriented fashion by putting conflict-resolution logic either in your end_upload_rows script or in your end_upload table script.

You can have one resolve_conflict script for each table in the remote database.

See also
SQL example

The following statement defines a resolve_conflict script suited to the CustDB sample application for an Oracle installation. It calls a stored procedure ULResolveOrderConflict.

exec ml_add_table_script(
   'custdb', 'ULOrder', 'resolve_conflict',
   'begin ULResolveOrderConflict();
end; ')
CREATE OR REPLACE PROCEDURE ULResolveOrderConflict()
AS
  new_order_id integer;
  new_status   varchar(20);
  new_notes   varchar(50);
BEGIN
  -- approval overrides denial
  SELECT order_id, status, notes
    INTO new_order_id, new_status, new_notes
    FROM ULNewOrder
   WHERE syncuser_id = SyncUserID;
  IF new_status = 'Approved' THEN
    UPDATE ULOrder o
       SET o.status = new_status, o.notes =
new_notes
     WHERE o.order_id = new_order_id;
  END IF;
  DELETE FROM ULOldOrder;
  DELETE FROM ULNewOrder;
END;
Java example

The following call to a MobiLink system procedure registers a Java method called resolveConflict as the script for the resolve_conflict table event when synchronizing the script version ver1.

CALL ml_add_java_table_script(
   'ver1',
   'table1',
   'resolve_conflict',
   'ExamplePackage.ExampleClass.resolveConflict' )

Following is the sample Java method resolveConflict. It calls a Java method that uses the JDBC connection provided by MobiLink to resolve the conflict.

public String resolveConflict( 
  String user,
  String table) {
  resolveRows(_syncConn, user ); 
}
.NET example

The following call to a MobiLink system procedure registers a .NET method called ResolveConflict as the script for the resolve_conflict table event when synchronizing the script version ver1.

CALL ml_add_dnet_table_script(
   'ver1',
   'table1',
   'resolve_conflict',
   'TestScripts.Test.ResolveConflict' )

Following is the sample .NET method ResolveConflict. It calls a .NET method that resolves the conflict.

public string ResolveConflict( 
  String user,
  String table) {
  ResolveRows(_syncConn, user ); 
}