Skip to content

H
h2database
提交 0531f3fc authored 作者: Evgenij Ryazanov's avatar Evgenij Ryazanov
浏览文件
操作

Move MEDIAN-related code to AggregateDataMedian

上级 503cd5f4
显示空白字符变更
内嵌 并排
正在显示 包含 100 行增加 和 88 行删除
h2/src/main/org/h2/expression/Aggregate.java
浏览文件 @ 0531f3fc
......@@ -20,7 +20,6 @@ import org.h2.result.SearchRow;
import org.h2.result.SortOrder;
import org.h2.table.Column;
import org.h2.table.ColumnResolver;
import org.h2.table.IndexColumn;
import org.h2.table.Table;
import org.h2.table.TableFilter;
import org.h2.util.StatementBuilder;
......@@ -312,50 +311,7 @@ public class Aggregate extends Expression {
return v;
}
case MEDIAN: {
Index index = getMedianColumnIndex();
long count = index.getRowCount(session);
if (count == 0) {
return ValueNull.INSTANCE;
}
Cursor cursor = index.find(session, null, null);
cursor.next();
// Skip nulls
SearchRow row;
while (count > 0) {
row = cursor.getSearchRow();
if (row == null) {
return ValueNull.INSTANCE;
}
if (row.getValue(index.getColumns()[0].getColumnId()) == ValueNull.INSTANCE) {
count--;
cursor.next();
} else
break;
}
if (count == 0) {
return ValueNull.INSTANCE;
}
long skip = (count - 1) / 2;
for (int i = 0; i < skip; i++) {
cursor.next();
}
row = cursor.getSearchRow();
Value v;
if (row == null) {
v = ValueNull.INSTANCE;
} else {
v = row.getValue(index.getColumns()[0].getColumnId());
}
if ((count & 1) == 0) {
cursor.next();
row = cursor.getSearchRow();
if (row == null) {
return v;
}
Value v2 = row.getValue(index.getColumns()[0].getColumnId());
return AggregateDataMedian.getMedian(v, v2, dataType, session.getDatabase().getCompareMode());
}
return v;
return AggregateDataMedian.getFromIndex(session, on, dataType);
}
default:
DbException.throwInternalError("type=" + type);
......@@ -649,46 +605,6 @@ public class Aggregate extends Expression {
return null;
}
private Index getMedianColumnIndex() {
if (on instanceof ExpressionColumn) {
ExpressionColumn col = (ExpressionColumn) on;
Column column = col.getColumn();
TableFilter filter = col.getTableFilter();
if (filter != null) {
Table table = filter.getTable();
ArrayList<Index> indexes = table.getIndexes();
Index result = null;
if (indexes != null) {
for (int i = 1, size = indexes.size(); i < size; i++) {
Index index = indexes.get(i);
if (!index.canFindNext()) {
continue;
}
if (!index.isFirstColumn(column)) {
continue;
}
IndexColumn ic = index.getIndexColumns()[0];
if (column.isNullable()) {
int sortType = ic.sortType;
// Nulls last is not supported
if ((sortType & SortOrder.NULLS_LAST) != 0)
continue;
// Descending without nulls first is not supported
if ((sortType & SortOrder.DESCENDING) != 0 && (sortType & SortOrder.NULLS_FIRST) == 0) {
continue;
}
}
if (result == null || result.getColumns().length > index.getColumns().length) {
result = index;
}
}
}
return result;
}
}
return null;
}
@Override
public boolean isEverything(ExpressionVisitor visitor) {
if (visitor.getType() == ExpressionVisitor.OPTIMIZABLE_MIN_MAX_COUNT_ALL) {
......@@ -708,7 +624,7 @@ public class Aggregate extends Expression {
if (distinct) {
return false;
}
return getMedianColumnIndex() != null;
return AggregateDataMedian.getMedianColumnIndex(on) != null;
default:
return false;
}
......
h2/src/main/org/h2/expression/AggregateDataMedian.java
浏览文件 @ 0531f3fc
......@@ -13,6 +13,15 @@ import java.util.Comparator;
import java.util.HashSet;
import org.h2.engine.Database;
import org.h2.engine.Session;
import org.h2.index.Cursor;
import org.h2.index.Index;
import org.h2.result.SearchRow;
import org.h2.result.SortOrder;
import org.h2.table.Column;
import org.h2.table.IndexColumn;
import org.h2.table.Table;
import org.h2.table.TableFilter;
import org.h2.util.DateTimeUtils;
import org.h2.value.CompareMode;
import org.h2.value.Value;
......@@ -33,6 +42,93 @@ import org.h2.value.ValueTimestampTimeZone;
class AggregateDataMedian extends AggregateData {
private Collection<Value> values;
static Index getMedianColumnIndex(Expression on) {
if (on instanceof ExpressionColumn) {
ExpressionColumn col = (ExpressionColumn) on;
Column column = col.getColumn();
TableFilter filter = col.getTableFilter();
if (filter != null) {
Table table = filter.getTable();
ArrayList<Index> indexes = table.getIndexes();
Index result = null;
if (indexes != null) {
for (int i = 1, size = indexes.size(); i < size; i++) {
Index index = indexes.get(i);
if (!index.canFindNext()) {
continue;
}
if (!index.isFirstColumn(column)) {
continue;
}
IndexColumn ic = index.getIndexColumns()[0];
if (column.isNullable()) {
int sortType = ic.sortType;
// Nulls last is not supported
if ((sortType & SortOrder.NULLS_LAST) != 0)
continue;
// Descending without nulls first is not supported
if ((sortType & SortOrder.DESCENDING) != 0 && (sortType & SortOrder.NULLS_FIRST) == 0) {
continue;
}
}
if (result == null || result.getColumns().length > index.getColumns().length) {
result = index;
}
}
}
return result;
}
}
return null;
}
static Value getFromIndex(Session session, Expression on, int dataType) {
Index index = getMedianColumnIndex(on);
long count = index.getRowCount(session);
if (count == 0) {
return ValueNull.INSTANCE;
}
Cursor cursor = index.find(session, null, null);
cursor.next();
// Skip nulls
SearchRow row;
while (count > 0) {
row = cursor.getSearchRow();
if (row == null) {
return ValueNull.INSTANCE;
}
if (row.getValue(index.getColumns()[0].getColumnId()) == ValueNull.INSTANCE) {
count--;
cursor.next();
} else
break;
}
if (count == 0) {
return ValueNull.INSTANCE;
}
long skip = (count - 1) / 2;
for (int i = 0; i < skip; i++) {
cursor.next();
}
row = cursor.getSearchRow();
Value v;
if (row == null) {
v = ValueNull.INSTANCE;
} else {
v = row.getValue(index.getColumns()[0].getColumnId());
}
if ((count & 1) == 0) {
cursor.next();
row = cursor.getSearchRow();
if (row == null) {
return v;
}
Value v2 = row.getValue(index.getColumns()[0].getColumnId());
return getMedian(v, v2, dataType, session.getDatabase().getCompareMode());
}
return v;
}
@Override
void add(Database database, int dataType, boolean distinct, Value v) {
if (v == ValueNull.INSTANCE) {
......@@ -104,7 +200,7 @@ class AggregateDataMedian extends AggregateData {
+ DateTimeUtils.absoluteDayFromDateValue(ts1.getDateValue());
long nanos = (ts0.getTimeNanos() + ts1.getTimeNanos()) / 2;
if ((dateSum & 1) != 0) {
nanos += (DateTimeUtils.NANOS_PER_DAY / 2);
nanos += DateTimeUtils.NANOS_PER_DAY / 2;
if (nanos >= DateTimeUtils.NANOS_PER_DAY) {
nanos -= DateTimeUtils.NANOS_PER_DAY;
dateSum++;
......@@ -119,7 +215,7 @@ class AggregateDataMedian extends AggregateData {
+ DateTimeUtils.absoluteDayFromDateValue(ts1.getDateValue());
long nanos = (ts0.getTimeNanos() + ts1.getTimeNanos()) / 2;
if ((dateSum & 1) != 0) {
nanos += (DateTimeUtils.NANOS_PER_DAY / 2);
nanos += DateTimeUtils.NANOS_PER_DAY / 2;
if (nanos >= DateTimeUtils.NANOS_PER_DAY) {
nanos -= DateTimeUtils.NANOS_PER_DAY;
dateSum++;
......
Markdown 格式
0% 或
您添加了 0 人 到此讨论。请谨慎行事。
请先完成此评论的编辑！
请 注册 或者 后发表评论