Examples with LocalResult org.h2.result.LocalResult used on opensource projects

Example 6 with LocalResult

use of org.h2.result.LocalResult in project h2database by h2database.

the class TableFunction method getTable.

private ValueResultSet getTable(Session session, Expression[] argList, boolean onlyColumnList, boolean distinctRows) {
    int len = columnList.length;
    Expression[] header = new Expression[len];
    Database db = session.getDatabase();
    for (int i = 0; i < len; i++) {
        Column c = columnList[i];
        ExpressionColumn col = new ExpressionColumn(db, c);
        header[i] = col;
    }
    LocalResult result = new LocalResult(session, header, len);
    if (distinctRows) {
        result.setDistinct();
    }
    if (!onlyColumnList) {
        Value[][] list = new Value[len][];
        int rows = 0;
        for (int i = 0; i < len; i++) {
            Value v = argList[i].getValue(session);
            if (v == ValueNull.INSTANCE) {
                list[i] = new Value[0];
            } else {
                ValueArray array = (ValueArray) v.convertTo(Value.ARRAY);
                Value[] l = array.getList();
                list[i] = l;
                rows = Math.max(rows, l.length);
            }
        }
        for (int row = 0; row < rows; row++) {
            Value[] r = new Value[len];
            for (int j = 0; j < len; j++) {
                Value[] l = list[j];
                Value v;
                if (l.length <= row) {
                    v = ValueNull.INSTANCE;
                } else {
                    Column c = columnList[j];
                    v = l[row];
                    v = c.convert(v);
                    v = v.convertPrecision(c.getPrecision(), false);
                    v = v.convertScale(true, c.getScale());
                }
                r[j] = v;
            }
            result.addRow(r);
        }
    }
    result.done();
    return ValueResultSet.get(getSimpleResultSet(result, Integer.MAX_VALUE));
}

Example 7 with LocalResult

use of org.h2.result.LocalResult in project h2database by h2database.

the class ViewIndex method findRecursive.

private Cursor findRecursive(SearchRow first, SearchRow last) {
    assert recursive;
    ResultInterface recursiveResult = view.getRecursiveResult();
    if (recursiveResult != null) {
        recursiveResult.reset();
        return new ViewCursor(this, recursiveResult, first, last);
    }
    if (query == null) {
        Parser parser = new Parser(createSession);
        parser.setRightsChecked(true);
        parser.setSuppliedParameterList(originalParameters);
        query = (Query) parser.prepare(querySQL);
        query.setNeverLazy(true);
    }
    if (!query.isUnion()) {
        throw DbException.get(ErrorCode.SYNTAX_ERROR_2, "recursive queries without UNION");
    }
    SelectUnion union = (SelectUnion) query;
    Query left = union.getLeft();
    left.setNeverLazy(true);
    // to ensure the last result is not closed
    left.disableCache();
    ResultInterface resultInterface = left.query(0);
    LocalResult localResult = union.getEmptyResult();
    // ensure it is not written to disk,
    // because it is not closed normally
    localResult.setMaxMemoryRows(Integer.MAX_VALUE);
    while (resultInterface.next()) {
        Value[] cr = resultInterface.currentRow();
        localResult.addRow(cr);
    }
    Query right = union.getRight();
    right.setNeverLazy(true);
    resultInterface.reset();
    view.setRecursiveResult(resultInterface);
    // to ensure the last result is not closed
    right.disableCache();
    while (true) {
        resultInterface = right.query(0);
        if (!resultInterface.hasNext()) {
            break;
        }
        while (resultInterface.next()) {
            Value[] cr = resultInterface.currentRow();
            localResult.addRow(cr);
        }
        resultInterface.reset();
        view.setRecursiveResult(resultInterface);
    }
    view.setRecursiveResult(null);
    localResult.done();
    return new ViewCursor(this, localResult, first, last);
}

Example 8 with LocalResult

use of org.h2.result.LocalResult in project h2database by h2database.

the class ScriptCommand method queryMeta.

@Override
public ResultInterface queryMeta() {
    LocalResult r = createResult();
    r.done();
    return r;
}

Example 9 with LocalResult

use of org.h2.result.LocalResult in project h2database by h2database.

the class Select method queryGroup.

private void queryGroup(int columnCount, LocalResult result) {
    ValueHashMap<HashMap<Expression, Object>> groups = ValueHashMap.newInstance();
    int rowNumber = 0;
    setCurrentRowNumber(0);
    currentGroup = null;
    ValueArray defaultGroup = ValueArray.get(new Value[0]);
    int sampleSize = getSampleSizeValue(session);
    while (topTableFilter.next()) {
        setCurrentRowNumber(rowNumber + 1);
        if (isConditionMet()) {
            Value key;
            rowNumber++;
            if (groupIndex == null) {
                key = defaultGroup;
            } else {
                Value[] keyValues = new Value[groupIndex.length];
                // update group
                for (int i = 0; i < groupIndex.length; i++) {
                    int idx = groupIndex[i];
                    Expression expr = expressions.get(idx);
                    keyValues[i] = expr.getValue(session);
                }
                key = ValueArray.get(keyValues);
            }
            HashMap<Expression, Object> values = groups.get(key);
            if (values == null) {
                values = new HashMap<>();
                groups.put(key, values);
            }
            currentGroup = values;
            currentGroupRowId++;
            for (int i = 0; i < columnCount; i++) {
                if (groupByExpression == null || !groupByExpression[i]) {
                    Expression expr = expressions.get(i);
                    expr.updateAggregate(session);
                }
            }
            if (sampleSize > 0 && rowNumber >= sampleSize) {
                break;
            }
        }
    }
    if (groupIndex == null && groups.size() == 0) {
        groups.put(defaultGroup, new HashMap<Expression, Object>());
    }
    ArrayList<Value> keys = groups.keys();
    for (Value v : keys) {
        ValueArray key = (ValueArray) v;
        currentGroup = groups.get(key);
        Value[] keyValues = key.getList();
        Value[] row = new Value[columnCount];
        for (int j = 0; groupIndex != null && j < groupIndex.length; j++) {
            row[groupIndex[j]] = keyValues[j];
        }
        for (int j = 0; j < columnCount; j++) {
            if (groupByExpression != null && groupByExpression[j]) {
                continue;
            }
            Expression expr = expressions.get(j);
            row[j] = expr.getValue(session);
        }
        if (isHavingNullOrFalse(row)) {
            continue;
        }
        row = keepOnlyDistinct(row, columnCount);
        result.addRow(row);
    }
}

Example 10 with LocalResult

use of org.h2.result.LocalResult in project h2database by h2database.

the class SelectUnion method queryMeta.

@Override
public ResultInterface queryMeta() {
    int columnCount = left.getColumnCount();
    LocalResult result = new LocalResult(session, expressionArray, columnCount);
    result.done();
    return result;
}