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

Example 46 with Description

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

the class IpPrefixFunctions method ipPrefix.

@Description("IP prefix for a given IP address and subnet size")
@ScalarFunction("ip_prefix")
@SqlType(StandardTypes.IPPREFIX)
public static Slice ipPrefix(@SqlType(StandardTypes.IPADDRESS) Slice value, @SqlType(StandardTypes.BIGINT) long subnetSize) {
    InetAddress address = toInetAddress(value);
    int addressLength = address.getAddress().length;
    if (addressLength == 4) {
        checkCondition(0 <= subnetSize && subnetSize <= 32, INVALID_FUNCTION_ARGUMENT, "IPv4 subnet size must be in range [0, 32]");
    } else if (addressLength == 16) {
        checkCondition(0 <= subnetSize && subnetSize <= 128, INVALID_FUNCTION_ARGUMENT, "IPv6 subnet size must be in range [0, 128]");
    } else {
        throw new PrestoException(GENERIC_INTERNAL_ERROR, "Invalid InetAddress length: " + addressLength);
    }
    return castFromVarcharToIpPrefix(utf8Slice(InetAddresses.toAddrString(address) + "/" + subnetSize));
}

Example 47 with Description

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

the class StringFunctions method hammingDistance.

@Description("computes Hamming distance between two strings")
@ScalarFunction
@LiteralParameters({ "x", "y" })
@SqlType(StandardTypes.BIGINT)
public static long hammingDistance(@SqlType("varchar(x)") Slice left, @SqlType("varchar(y)") Slice right) {
    int distance = 0;
    int leftPosition = 0;
    int rightPosition = 0;
    while (leftPosition < left.length() && rightPosition < right.length()) {
        int codePointLeft = tryGetCodePointAt(left, leftPosition);
        int codePointRight = tryGetCodePointAt(right, rightPosition);
        // the following code treats them as equal if they happen to be of the same length
        if (codePointLeft != codePointRight) {
            distance++;
        }
        leftPosition += codePointLeft >= 0 ? lengthOfCodePoint(codePointLeft) : -codePointLeft;
        rightPosition += codePointRight >= 0 ? lengthOfCodePoint(codePointRight) : -codePointRight;
    }
    checkCondition(leftPosition == left.length() && rightPosition == right.length(), INVALID_FUNCTION_ARGUMENT, "The input strings to hamming_distance function must have the same length");
    return distance;
}

Example 48 with Description

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

the class StringFunctions method substr.

@Description("suffix starting at given index")
@ScalarFunction
@LiteralParameters("x")
@SqlType("varchar(x)")
public static Slice substr(@SqlType("varchar(x)") Slice utf8, @SqlType(StandardTypes.BIGINT) long start) {
    if ((start == 0) || utf8.length() == 0) {
        return Slices.EMPTY_SLICE;
    }
    int startCodePoint = Ints.saturatedCast(start);
    if (startCodePoint > 0) {
        int indexStart = offsetOfCodePoint(utf8, startCodePoint - 1);
        if (indexStart < 0) {
            // before beginning of string
            return Slices.EMPTY_SLICE;
        }
        int 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 = utf8.length();
    return utf8.slice(indexStart, indexEnd - indexStart);
}

Example 49 with Description

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

the class VarbinaryFunctions method toBigEndian64.

@Description("encode value as a 64-bit 2's complement big endian varbinary")
@ScalarFunction("to_big_endian_64")
@SqlType(StandardTypes.VARBINARY)
public static Slice toBigEndian64(@SqlType(StandardTypes.BIGINT) long value) {
    Slice slice = Slices.allocate(Long.BYTES);
    slice.setLong(0, Long.reverseBytes(value));
    return slice;
}

Example 50 with Description

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

the class VarbinaryFunctions method spookyHashV2_32.

@Description("compute SpookyHashV2 32-bit hash")
@ScalarFunction
@SqlType(StandardTypes.VARBINARY)
public static Slice spookyHashV2_32(@SqlType(StandardTypes.VARBINARY) Slice slice) {
    Slice hash = Slices.allocate(Integer.BYTES);
    hash.setInt(0, Integer.reverseBytes(SpookyHashV2.hash32(slice, 0, slice.length(), 0)));
    return hash;
}