io.questdb.griffin.engine.functions.cast.CastDoubleToSymbolFunctionFactory Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of questdb Show documentation
QuestDB is high performance SQL time series database
The newest version!
/*******************************************************************************
 *     ___                  _   ____  ____
 *    / _ \ _   _  ___  ___| |_|  _ \| __ )
 *   | | | | | | |/ _ \/ __| __| | | |  _ \
 *   | |_| | |_| |  __/\__ \ |_| |_| | |_) |
 *    \__\_\\__,_|\___||___/\__|____/|____/
 *
 *  Copyright (c) 2014-2019 Appsicle
 *  Copyright (c) 2019-2024 QuestDB
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

package io.questdb.griffin.engine.functions.cast;

import io.questdb.cairo.CairoConfiguration;
import io.questdb.cairo.TableUtils;
import io.questdb.cairo.sql.Function;
import io.questdb.cairo.sql.Record;
import io.questdb.cairo.sql.SymbolTable;
import io.questdb.cairo.sql.SymbolTableSource;
import io.questdb.griffin.FunctionFactory;
import io.questdb.griffin.PlanSink;
import io.questdb.griffin.SqlException;
import io.questdb.griffin.SqlExecutionContext;
import io.questdb.griffin.engine.functions.SymbolFunction;
import io.questdb.griffin.engine.functions.UnaryFunction;
import io.questdb.griffin.engine.functions.constants.SymbolConstant;
import io.questdb.std.*;
import io.questdb.std.str.StringSink;
import org.jetbrains.annotations.Nullable;

public class CastDoubleToSymbolFunctionFactory implements FunctionFactory {
    @Override
    public String getSignature() {
        return "cast(Dk)";
    }

    @Override
    public Function newInstance(int position, ObjList args, IntList argPositions, CairoConfiguration configuration, SqlExecutionContext sqlExecutionContext) {
        final Function arg = args.getQuick(0);
        if (arg.isConstant()) {
            final StringSink sink = Misc.getThreadLocalSink();
            sink.put(arg.getDouble(null));
            return SymbolConstant.newInstance(sink);
        }
        return new Func(arg);
    }

    private static class Func extends SymbolFunction implements UnaryFunction {
        private final Function arg;
        private final StringSink sink = new StringSink();
        private final LongIntHashMap symbolTableShortcut = new LongIntHashMap();
        private final ObjList symbols = new ObjList<>();
        private int next = 1;

        public Func(Function arg) {
            this.arg = arg;
            symbols.add(null);
        }

        @Override
        public Function getArg() {
            return arg;
        }

        @Override
        public int getInt(Record rec) {
            final double value = arg.getDouble(rec);
            if (Numbers.isNull(value)) {
                return SymbolTable.VALUE_IS_NULL;
            }

            final long key = Double.doubleToLongBits(value);
            final int keyIndex = symbolTableShortcut.keyIndex(key);
            if (keyIndex < 0) {
                return symbolTableShortcut.valueAt(keyIndex) - 1;
            }

            symbolTableShortcut.putAt(keyIndex, key, next);
            sink.clear();
            sink.put(value);
            symbols.add(Chars.toString(sink));
            return next++ - 1;
        }

        @Override
        public CharSequence getSymbol(Record rec) {
            final double value = arg.getDouble(rec);
            if (Numbers.isNull(value)) {
                return null;
            }

            final long key = Double.doubleToLongBits(value);
            final int keyIndex = symbolTableShortcut.keyIndex(key);
            if (keyIndex < 0) {
                return symbols.getQuick(symbolTableShortcut.valueAt(keyIndex));
            }

            symbolTableShortcut.putAt(keyIndex, key, next++);
            sink.clear();
            sink.put(value);
            final String str = Chars.toString(sink);
            symbols.add(Chars.toString(sink));
            return str;
        }

        @Override
        public CharSequence getSymbolB(Record rec) {
            return getSymbol(rec);
        }

        @Override
        public void init(SymbolTableSource symbolTableSource, SqlExecutionContext executionContext) throws SqlException {
            arg.init(symbolTableSource, executionContext);
            symbolTableShortcut.clear();
            symbols.clear();
            symbols.add(null);
            next = 1;
        }

        @Override
        public boolean isSymbolTableStatic() {
            return false;
        }

        @Override
        public @Nullable SymbolTable newSymbolTable() {
            Func copy = new Func(arg);
            copy.symbolTableShortcut.putAll(this.symbolTableShortcut);
            copy.symbols.clear();
            copy.symbols.addAll(this.symbols);
            copy.next = this.next;
            return copy;
        }

        @Override
        public void toPlan(PlanSink sink) {
            sink.val(arg).val("::symbol");
        }

        @Override
        public CharSequence valueBOf(int key) {
            return valueOf(key);
        }

        @Override
        public CharSequence valueOf(int symbolKey) {
            return symbols.getQuick(TableUtils.toIndexKey(symbolKey));
        }
    }
}