Archives/gnosygnu_xowa
1
0
Fork 0
mirror of https://github.com/gnosygnu/xowa.git synced 2026-03-02 03:49:30 +00:00
Code Issues Projects Releases Wiki Activity

v2.7.2.1

Browse Source
This commit is contained in:
gnosygnu
2015-07-12 21:10:02 -04:00
commit 794b5a232f
3099 changed files with 238212 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

99
140_dbs/src/gplx/dbs/engines/tdbs/TdbSelect.java Normal file
View File

@@ -0,0 +1,99 @@
/*
XOWA: the XOWA Offline Wiki Application
Copyright (C) 2012 gnosygnu@gmail.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as
published by the Free Software Foundation, either version 3 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package gplx.dbs.engines.tdbs; import gplx.*; import gplx.dbs.*; import gplx.dbs.engines.*;
import gplx.core.criterias.*; import gplx.dbs.qrys.*; import gplx.dbs.sqls.*;
import gplx.lists.*; /*ComparerAble*/ import gplx.stores.*; /*GfoNdeRdr*/
class TdbSelectWkr implements Db_qryWkr {
public Object Exec(Db_engine engineObj, Db_qry cmdObj) {
TdbEngine engine = TdbEngine.cast_(engineObj); Db_qry__select_cmd cmd = (Db_qry__select_cmd)cmdObj;
if (cmd.From().Tbls().Count() > 1) throw Exc_.new_w_type("gplx.tdbs", "joins not supported for tdbs", "sql", cmd.Xto_sql());
TdbTable tbl = engine.FetchTbl(cmd.From().BaseTable().TblName());
GfoNdeList rv = (cmd.Where() == Db_qry_.WhereAll && cmd.Limit() == Db_qry__select_cmd.Limit_disabled) ? rv = tbl.Rows() : FilterRecords(tbl, cmd.Where(), cmd.Limit());
if (cmd.GroupBy() != null)
rv = TdbGroupByWkr.GroupByExec(cmd, rv, tbl);
if (cmd.OrderBy() != null) { // don't use null pattern here; if null ORDER BY, then don't call .Sort on GfoNdeList
ComparerAble comparer = Sql_order_by_sorter.new_((Sql_order_by_itm[])cmd.OrderBy().Flds().To_ary(Sql_order_by_itm.class));
rv.Sort_by(comparer);
}
return GfoNdeRdr_.peers_(rv, false);
}
GfoNdeList FilterRecords(TdbTable tbl, Criteria crt, int limit) {
GfoNdeList rv = GfoNdeList_.new_();
int count = 0;
for (int i = 0; i < tbl.Rows().Count(); i++) {
GfoNde row = (GfoNde)tbl.Rows().FetchAt_asGfoNde(i);
if (crt.Matches(row)) rv.Add(row);
++count;
if (count == limit) break;
}
return rv;
}
public static final TdbSelectWkr _ = new TdbSelectWkr(); TdbSelectWkr() {}
}
class TdbGroupByWkr {
public static GfoNdeList GroupByExec(Db_qry__select_cmd select, GfoNdeList selectRows, TdbTable tbl) {
GfoNdeList rv = GfoNdeList_.new_();
Ordered_hash groupByHash = Ordered_hash_.new_();
List_adp groupByFlds = select.GroupBy().Flds();
GfoFldList selectFldsForNewRow = select.Cols().Flds().XtoGfoFldLst(tbl);
Sql_select_fld_list selectFlds = select.Cols().Flds();
for (int rowIdx = 0; rowIdx < selectRows.Count(); rowIdx++) {
GfoNde selectRow = selectRows.FetchAt_asGfoNde(rowIdx);
GfoNde groupByRow = FindOrNew(selectFldsForNewRow, groupByFlds, selectRow, groupByHash, rv);
for (int i = 0; i < selectFlds.Count(); i++) {
Sql_select_fld_base selectFld = selectFlds.Get_at(i);
Object val = groupByRow.Read(selectFld.Alias()); // groupByRow is keyed by Alias; EX: Count(Id) AS CountOf
groupByRow.WriteAt(i, selectFld.GroupBy_eval(val, selectRow.Read(selectFld.Fld()), selectFld.ValType()));
}
}
return rv;
}
static GfoNde FindOrNew(GfoFldList selectFldsForNewRow, List_adp groupByFlds, GfoNde selectRow, Ordered_hash groupByRows, GfoNdeList rslt) {
int len = groupByFlds.Count();
Ordered_hash curHash = groupByRows;
GfoNde rv = null;
for (int i = 0; i < len; i++) {
String fld = (String)groupByFlds.Get_at(i);
boolean last = i == len - 1;
Object val = selectRow.Read(fld);
Object o = curHash.Get_by(val);
if (last) {
if (o == null) {
Object[] valAry = new Object[selectFldsForNewRow.Count()];
rv = GfoNde_.vals_(selectFldsForNewRow, valAry);
curHash.Add(val, rv);
rslt.Add(rv);
}
else
rv = GfoNde_.as_(o);
}
else {
if (o == null) {
Ordered_hash nextHash = Ordered_hash_.new_();
curHash.Add(val, nextHash);
curHash = nextHash;
}
else {
curHash = (Ordered_hash)o;
}
}
}
return rv;
}
}