Examples with Description io.trino.spi.function.Description used on opensource projects

Example 1 with Description

use of io.trino.spi.function.Description in project trino by trinodb.

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 2 with Description

use of io.trino.spi.function.Description in project trino by trinodb.

the class StringFunctions method fromUtf8.

@Description("Decodes the UTF-8 encoded string")
@ScalarFunction
@LiteralParameters("x")
@SqlType(StandardTypes.VARCHAR)
public static Slice fromUtf8(@SqlType(StandardTypes.VARBINARY) Slice slice, @SqlType("varchar(x)") Slice replacementCharacter) {
    int count = countCodePoints(replacementCharacter);
    if (count > 1) {
        throw new TrinoException(INVALID_FUNCTION_ARGUMENT, "Replacement character string must empty or a single character");
    }
    OptionalInt replacementCodePoint;
    if (count == 1) {
        try {
            replacementCodePoint = OptionalInt.of(getCodePointAt(replacementCharacter, 0));
        } catch (InvalidUtf8Exception e) {
            throw new TrinoException(INVALID_FUNCTION_ARGUMENT, "Invalid replacement character");
        }
    } else {
        replacementCodePoint = OptionalInt.empty();
    }
    return SliceUtf8.fixInvalidUtf8(slice, replacementCodePoint);
}

Example 3 with Description

use of io.trino.spi.function.Description in project trino by trinodb.

the class StringFunctions method replace.

@Description("Greedily replaces occurrences of a pattern with a string")
@ScalarFunction
@LiteralParameters({ "x", "y", "z", "u" })
@Constraint(variable = "u", expression = "min(2147483647, x + z * (x + 1))")
@SqlType("varchar(u)")
public static Slice replace(@SqlType("varchar(x)") Slice str, @SqlType("varchar(y)") Slice search, @SqlType("varchar(z)") Slice replace) {
    // Empty search?
    if (search.length() == 0) {
        // With empty `search` we insert `replace` in front of every character and the end
        Slice buffer = Slices.allocate((countCodePoints(str) + 1) * replace.length() + str.length());
        // Always start with replace
        buffer.setBytes(0, replace);
        int indexBuffer = replace.length();
        // After every code point insert `replace`
        int index = 0;
        while (index < str.length()) {
            int codePointLength = lengthOfCodePointSafe(str, index);
            // Append current code point
            buffer.setBytes(indexBuffer, str, index, codePointLength);
            indexBuffer += codePointLength;
            // Append `replace`
            buffer.setBytes(indexBuffer, replace);
            indexBuffer += replace.length();
            // Advance pointer to current code point
            index += codePointLength;
        }
        return buffer;
    }
    // Allocate a reasonable buffer
    Slice buffer = Slices.allocate(str.length());
    int index = 0;
    int indexBuffer = 0;
    while (index < str.length()) {
        int matchIndex = str.indexOf(search, index);
        // Found a match?
        if (matchIndex < 0) {
            // No match found so copy the rest of string
            int bytesToCopy = str.length() - index;
            buffer = Slices.ensureSize(buffer, indexBuffer + bytesToCopy);
            buffer.setBytes(indexBuffer, str, index, bytesToCopy);
            indexBuffer += bytesToCopy;
            break;
        }
        int bytesToCopy = matchIndex - index;
        buffer = Slices.ensureSize(buffer, indexBuffer + bytesToCopy + replace.length());
        // Non empty match?
        if (bytesToCopy > 0) {
            buffer.setBytes(indexBuffer, str, index, bytesToCopy);
            indexBuffer += bytesToCopy;
        }
        // Non empty replace?
        if (replace.length() > 0) {
            buffer.setBytes(indexBuffer, replace);
            indexBuffer += replace.length();
        }
        // Continue searching after match
        index = matchIndex + search.length();
    }
    return buffer.slice(0, indexBuffer);
}

Example 4 with Description

use of io.trino.spi.function.Description in project trino by trinodb.

the class UrlFunctions method urlExtractParameter.

@SqlNullable
@Description("Extract query parameter from url")
@ScalarFunction
@LiteralParameters({ "x", "y" })
@SqlType("varchar(x)")
public static Slice urlExtractParameter(@SqlType("varchar(x)") Slice url, @SqlType("varchar(y)") Slice parameterName) {
    URI uri = parseUrl(url);
    if ((uri == null) || (uri.getRawQuery() == null)) {
        return null;
    }
    String parameter = parameterName.toStringUtf8();
    Iterable<String> queryArgs = QUERY_SPLITTER.split(uri.getRawQuery());
    for (String queryArg : queryArgs) {
        Iterator<String> arg = ARG_SPLITTER.split(queryArg).iterator();
        if (arg.next().equals(parameter)) {
            if (arg.hasNext()) {
                return decodeUrl(arg.next());
            }
            // first matched key is empty
            return Slices.EMPTY_SLICE;
        }
    }
    // no key matched
    return null;
}

Example 5 with Description

use of io.trino.spi.function.Description in project trino by trinodb.

the class VarbinaryFunctions method toIEEE754Binary64.

@Description("Encode value as a big endian varbinary according to IEEE 754 double-precision floating-point format")
@ScalarFunction("to_ieee754_64")
@SqlType(StandardTypes.VARBINARY)
public static Slice toIEEE754Binary64(@SqlType(StandardTypes.DOUBLE) double value) {
    Slice slice = Slices.allocate(Double.BYTES);
    slice.setLong(0, Long.reverseBytes(Double.doubleToLongBits(value)));
    return slice;
}