Examples with ScalarFunction com.facebook.presto.spi.function.ScalarFunction used on opensource projects

Example 21 with ScalarFunction

use of com.facebook.presto.spi.function.ScalarFunction in project presto by prestodb.

the class BenchmarkArraySort method oldArraySort.

@ScalarFunction
@SqlType("array(varchar)")
public static Block oldArraySort(@SqlType("array(varchar)") Block block) {
    List<Integer> positions = Ints.asList(new int[block.getPositionCount()]);
    for (int i = 0; i < block.getPositionCount(); i++) {
        positions.set(i, i);
    }
    Collections.sort(positions, new Comparator<Integer>() {

        @Override
        public int compare(Integer p1, Integer p2) {
            //TODO: This could be quite slow, it should use parametric equals
            return VARCHAR.compareTo(block, p1, block, p2);
        }
    });
    BlockBuilder blockBuilder = VARCHAR.createBlockBuilder(new BlockBuilderStatus(), block.getPositionCount());
    for (int position : positions) {
        VARCHAR.appendTo(block, position, blockBuilder);
    }
    return blockBuilder.build();
}

Example 22 with ScalarFunction

use of com.facebook.presto.spi.function.ScalarFunction in project presto by prestodb.

the class BenchmarkArrayDistinct method oldArrayDistinct.

@ScalarFunction
@SqlType("array(varchar)")
public static Block oldArrayDistinct(@SqlType("array(varchar)") Block array) {
    if (array.getPositionCount() == 0) {
        return array;
    }
    TypedSet typedSet = new TypedSet(VARCHAR, array.getPositionCount());
    BlockBuilder distinctElementBlockBuilder = VARCHAR.createBlockBuilder(new BlockBuilderStatus(), array.getPositionCount());
    for (int i = 0; i < array.getPositionCount(); i++) {
        if (!typedSet.contains(array, i)) {
            typedSet.add(array, i);
            VARCHAR.appendTo(array, i, distinctElementBlockBuilder);
        }
    }
    return distinctElementBlockBuilder.build();
}

Example 23 with ScalarFunction

use of com.facebook.presto.spi.function.ScalarFunction in project presto by prestodb.

the class StringFunctions method substr.

@Description("substring of given length starting at an index")
@ScalarFunction
@LiteralParameters("x")
@SqlType("varchar(x)")
public static Slice substr(@SqlType("varchar(x)") Slice utf8, @SqlType(StandardTypes.BIGINT) long start, @SqlType(StandardTypes.BIGINT) long length) {
    if (start == 0 || (length <= 0) || (utf8.length() == 0)) {
        return Slices.EMPTY_SLICE;
    }
    int startCodePoint = Ints.saturatedCast(start);
    int lengthCodePoints = Ints.saturatedCast(length);
    if (startCodePoint > 0) {
        int indexStart = offsetOfCodePoint(utf8, startCodePoint - 1);
        if (indexStart < 0) {
            // before beginning of string
            return Slices.EMPTY_SLICE;
        }
        int indexEnd = offsetOfCodePoint(utf8, indexStart, lengthCodePoints);
        if (indexEnd < 0) {
            // after end of string
            indexEnd = utf8.length();
        }
        return utf8.slice(indexStart, indexEnd - indexStart);
    }
    // negative start is relative to end of string
    int codePoints = countCodePoints(utf8);
    startCodePoint += codePoints;
    // before beginning of string
    if (startCodePoint < 0) {
        return Slices.EMPTY_SLICE;
    }
    int indexStart = offsetOfCodePoint(utf8, startCodePoint);
    int indexEnd;
    if (startCodePoint + lengthCodePoints < codePoints) {
        indexEnd = offsetOfCodePoint(utf8, indexStart, lengthCodePoints);
    } else {
        indexEnd = utf8.length();
    }
    return utf8.slice(indexStart, indexEnd - indexStart);
}

Example 24 with ScalarFunction

use of com.facebook.presto.spi.function.ScalarFunction in project presto by prestodb.

the class TimestampWithTimeZoneOperators method castToDate.

@ScalarFunction("date")
@ScalarOperator(CAST)
@SqlType(StandardTypes.DATE)
public static long castToDate(@SqlType(StandardTypes.TIMESTAMP_WITH_TIME_ZONE) long value) {
    // round down the current timestamp to days
    ISOChronology chronology = unpackChronology(value);
    long date = chronology.dayOfYear().roundFloor(unpackMillisUtc(value));
    // date is currently midnight in timezone of the original value
    // convert to UTC
    long millis = date + chronology.getZone().getOffset(date);
    return TimeUnit.MILLISECONDS.toDays(millis);
}

Example 25 with ScalarFunction

use of com.facebook.presto.spi.function.ScalarFunction in project presto by prestodb.

the class ColorFunctions method bar.

@ScalarFunction
@SqlType(StandardTypes.VARCHAR)
public static Slice bar(@SqlType(StandardTypes.DOUBLE) double percent, @SqlType(StandardTypes.BIGINT) long width, @SqlType(ColorType.NAME) long lowColor, @SqlType(ColorType.NAME) long highColor) {
    long count = (int) (percent * width);
    count = Math.min(width, count);
    count = Math.max(0, count);
    StringBuilder builder = new StringBuilder();
    for (int i = 0; i < count; i++) {
        float fraction = (float) (i * 1.0 / (width - 1));
        int color = interpolate(fraction, lowColor, highColor);
        builder.append(ansiColorEscape(color)).append('█');
    }
    // reset
    builder.append(ANSI_RESET);
    // pad to force column to be the requested width
    for (long i = count; i < width; ++i) {
        builder.append(' ');
    }
    return utf8Slice(builder.toString());
}