private void tsbCopyUnionSubquery_Click(object sender, EventArgs e)
{
// add empty UnionSubQuery
UnionSubQuery usq = queryBuilder1.ActiveUnionSubQuery.ParentGroup.Add();
// copy the content of existing union sub-query to a new one
SQLSubQuerySelectExpression usqAst = queryBuilder1.ActiveUnionSubQuery.ResultQueryAST;
usqAst.RestoreColumnPrefixRecursive(true);
List <SQLWithClauseItem> lCte = new List <SQLWithClauseItem>();
List <SQLFromSource> lFromObj = new List <SQLFromSource>();
queryBuilder1.ActiveUnionSubQuery.GatherPrepareAndFixupContext(lCte, lFromObj, false);
usqAst.PrepareAndFixupRecursive(lCte, lFromObj);
usq.LoadFromAST(usqAst);
queryBuilder1.ActiveUnionSubQuery = usq;
}
private void LoadQueryWithUnions()
{
UnionSubQuery unionSubQuery = _query.QueryRoot.FirstSelect();
DataSource ds1 = _query.AddObject(unionSubQuery, "MyDB.MySchema.Customers");
// create output column
QueryColumnListItem ci1 = unionSubQuery.QueryColumnList.AddField(ds1, "City");
ci1.Selected = true;
UnionSubQuery union1 = unionSubQuery.ParentGroup.Add();
DataSource ds2 = _query.AddObject(union1, "MyDB.MySchema.Orders");
// create output column with grouping
QueryColumnListItem ci2 = union1.QueryColumnList.AddField(ds2, "City");
ci2.Selected = true;
ci2.Grouping = true;
// Copy UnionSubQuery
// add an empty UnionSubQuery
UnionSubQuery usq = unionSubQuery.ParentGroup.Add();
// copy the content of existing union sub-query to a new one
SQLSubQuerySelectExpression usqAst = unionSubQuery.ResultQueryAST;
usqAst.RestoreColumnPrefixRecursive(true);
List <SQLWithClauseItem> lCte = new List <SQLWithClauseItem>();
List <SQLFromSource> lFromObj = new List <SQLFromSource>();
unionSubQuery.GatherPrepareAndFixupContext(lCte, lFromObj, false);
usqAst.PrepareAndFixupRecursive(lCte, lFromObj);
usq.LoadFromAST(usqAst);
QueryColumnListItem ci3 = usq.QueryColumnList.AddField(ds1, "CustomerAddress");
ci3.Selected = true;
}