Package com.couchbase.lite

Class Function

java.lang.Object
com.couchbase.lite.Function
public final class Function extends Object
Query functions.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Function()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    static Expression
    abs(Expression operand)
    Creates an ABS(expr) function that returns the absolute value of the given numeric expression.
    static Expression
    acos(Expression operand)
    Creates an ACOS(expr) function that returns the inverse cosine of the given numeric expression.
    static Expression
    asin(Expression operand)
    Creates an ASIN(expr) function that returns the inverse sin of the given numeric expression.
    static Expression
    atan(Expression operand)
    Creates an ATAN(expr) function that returns the inverse tangent of the numeric expression.
    static Expression
    atan2(Expression y, Expression x)
    Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta).
    static Expression
    avg(Expression operand)
    Creates an AVG(expr) function expression that returns the average of all the number values in the group of the values expressed by the given expression.
    static Expression
    ceil(Expression operand)
    Creates a CEIL(expr) function that returns the ceiling value of the given numeric expression.
    static Expression
    contains(Expression operand, Expression substring)
    Creates a CONTAINS(expr, substr) function that evaluates whether the given string expression conatins the given substring expression or not.
    static Expression
    cos(Expression operand)
    Creates a COS(expr) function that returns the cosine of the given numeric expression.
    static Expression
    cosineDistance(Expression expression1, Expression expression2)
    ENTERPRISE EDITION API

    static Expression
    count(Expression operand)
    Creates a COUNT(expr) function expression that returns the count of all values in the group of the values expressed by the given expression.
    static Expression
    degrees(Expression operand)
    Creates a DEGREES(expr) function that returns the degrees value of the given radiants value expression.
    static Expression
    e()
    Creates a E() function that return the value of the mathematical constant 'e'.
    static Expression
    euclideanDistance(Expression expression1, Expression expression2)
    ENTERPRISE EDITION API

    static Expression
    exp(Expression operand)
    Creates a EXP(expr) function that returns the value of 'e' power by the given numeric expression.
    static Expression
    floor(Expression operand)
    Creates a FLOOR(expr) function that returns the floor value of the given numeric expression.
    static Expression
    length(Expression operand)
    Creates a LENGTH(expr) function that returns the length of the given string expression.
    static Expression
    ln(Expression operand)
    Creates a LN(expr) function that returns the natural log of the given numeric expression.
    static Expression
    log(Expression operand)
    Creates a LOG(expr) function that returns the base 10 log of the given numeric expression.
    static Expression
    lower(Expression operand)
    Creates a LOWER(expr) function that returns the lowercase string of the given string expression.
    static Expression
    ltrim(Expression operand)
    Creates a LTRIM(expr) function that removes the whitespace from the beginning of the given string expression.
    static Expression
    max(Expression operand)
    Creates a MAX(expr) function expression that returns the maximum value in the group of the values expressed by the given expression.
    static Expression
    millisToString(Expression operand)
    Creates a MILLIS_TO_STR(expr) function that will convert a numeric input representing milliseconds since the Unix epoch into a full ISO8601 date and time string in the device local time zone.
    static Expression
    millisToUTC(Expression operand)
    Creates a MILLIS_TO_UTC(expr) function that will convert a numeric input representing milliseconds since the Unix epoch into a full ISO8601 date and time string in UTC time.
    static Expression
    min(Expression operand)
    Creates a MIN(expr) function expression that returns the minimum value in the group of the values expressed by the given expression.
    static Expression
    pi()
    Creates a PI() function that returns the mathematical constant Pi.
    static Expression
    power(Expression base, Expression exp)
    Creates a POWER(base, exponent) function that returns the value of the given base expression power the given exponent expression.
    static PredictionFunction
    prediction(String model, Expression input)
    ENTERPRISE EDITION API

    static Expression
    radians(Expression operand)
    Creates a RADIANS(expr) function that returns the radians value of the given degrees value expression.
    static Expression
    round(Expression operand)
    Creates a ROUND(expr) function that returns the rounded value of the given numeric expression.
    static Expression
    round(Expression operand, Expression digits)
    Creates a ROUND(expr, digits) function that returns the rounded value to the given number of digits of the given numeric expression.
    static Expression
    rtrim(Expression operand)
    Creates a RTRIM(expr) function that removes the whitespace from the end of the given string expression.
    static Expression
    sign(Expression operand)
    Creates a SIGN(expr) function that returns the sign (1: positive, -1: negative, 0: zero) of the given numeric expression.
    static Expression
    sin(Expression operand)
    Creates a SIN(expr) function that returns the sin of the given numeric expression.
    static Expression
    sqrt(Expression operand)
    Creates a SQRT(expr) function that returns the square root of the given numeric expression.
    static Expression
    squaredEuclideanDistance(Expression expression1, Expression expression2)
    ENTERPRISE EDITION API

    static Expression
    stringToMillis(Expression operand)
    Creates a STR_TO_MILLIS(expr) that will convert an ISO8601 datetime string into the number of milliseconds since the unix epoch.
    static Expression
    stringToUTC(Expression operand)
    Creates a STR_TO_UTC(expr) that will convert an ISO8601 datetime string into a full ISO8601 UTC datetime string.
    static Expression
    sum(Expression operand)
    Creates a SUM(expr) function expression that return the sum of all number values in the group of the values expressed by the given expression.
    static Expression
    tan(Expression operand)
    Creates a TAN(expr) function that returns the tangent of the given numeric expression.
    static Expression
    trim(Expression operand)
    Creates a TRIM(expr) function that removes the whitespace from the beginning and the end of the given string expression.
    static Expression
    trunc(Expression operand)
    Creates a TRUNC(expr) function that truncates all of the digits after the decimal place of the given numeric expression.
    static Expression
    trunc(Expression operand, Expression digits)
    Creates a TRUNC(expr, digits) function that truncates the number of the digits after the decimal place of the given numeric expression.
    static Expression
    upper(Expression operand)
    Creates a UPPER(expr) function that returns the uppercase string of the given string expression.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Function

      public Function()

  • Method Details

    • prediction

      @NonNull public static PredictionFunction prediction(@NonNull String model, @NonNull Expression input)
      ENTERPRISE EDITION API

      Creates prediction function with the given model name and input. When running a query with the prediction function, the corresponding predictive model registered to CouchbaseLite Database class will be called with the given input to predict the result.

      The prediction result returned by the predictive model will be in a form dictionary object. To create an expression that refers to a property in the prediction result, the propertyPath(path) method of the created PredictionFunction object can be used.

      Parameters:
      model - The predictive model name registered to the CouchbaseLite Database.
      input - The expression evaluated to a dictionary.
      Returns:
      A PredictionFunction object.

    • euclideanDistance

      @NonNull public static Expression euclideanDistance(@NonNull Expression expression1, @NonNull Expression expression2)
      ENTERPRISE EDITION API

      Creates a function that returns the euclidean distance between the two input vectors. The result is a non-negative floating-point number. The expression1 and expression2 must be arrays of numbers, and must be the same length.

      Parameters:
      expression1 - The expression evaluated to an arrays of numbers.
      expression2 - The expression evaluated to an arrays of numbers.
      Returns:
      The euclidean distance between two given input vectors.

    • squaredEuclideanDistance

      @NonNull public static Expression squaredEuclideanDistance(@NonNull Expression expression1, @NonNull Expression expression2)
      ENTERPRISE EDITION API

      Creates a function that returns the squared euclidean distance between the two input vectors. The result is a non-negative floating-point number. The expression1 and expression2 must be arrays of numbers, and must be the same length.

      Parameters:
      expression1 - The expression evaluated to an arrays of numbers.
      expression2 - The expression evaluated to an arrays of numbers.
      Returns:
      The squared euclidean distance between two given input vectors.

    • cosineDistance

      @NonNull public static Expression cosineDistance(@NonNull Expression expression1, @NonNull Expression expression2)
      ENTERPRISE EDITION API

      Creates a function that returns the cosine distance which one minus the cosine similarity between the two input vectors. The result is a floating-point number ranges from −1.0 to 1.0. The expression1 and expression2 must be arrays of numbers, and must be the same length.

      Parameters:
      expression1 - The expression evaluated to an arrays of numbers.
      expression2 - The expression evaluated to an arrays of numbers.
      Returns:
      The cosine distance between two given input vectors.

    • avg

      @NonNull public static Expression avg(@NonNull Expression operand)
      Creates an AVG(expr) function expression that returns the average of all the number values in the group of the values expressed by the given expression.

      The expression.

      Returns:
      The AVG(expr) function.

    • count

      @NonNull public static Expression count(@Nullable Expression operand)
      Creates a COUNT(expr) function expression that returns the count of all values in the group of the values expressed by the given expression. Null expression is count *
      Parameters:
      operand - The expression.
      Returns:
      The COUNT(expr) function.

    • min

      @NonNull public static Expression min(@NonNull Expression operand)
      Creates a MIN(expr) function expression that returns the minimum value in the group of the values expressed by the given expression.
      Parameters:
      operand - The expression.
      Returns:
      The MIN(expr) function.

    • max

      @NonNull public static Expression max(@NonNull Expression operand)
      Creates a MAX(expr) function expression that returns the maximum value in the group of the values expressed by the given expression.
      Parameters:
      operand - The expression.
      Returns:
      The MAX(expr) function.

    • sum

      @NonNull public static Expression sum(@NonNull Expression operand)
      Creates a SUM(expr) function expression that return the sum of all number values in the group of the values expressed by the given expression.
      Parameters:
      operand - The expression.
      Returns:
      The SUM(expr) function.

    • abs

      @NonNull public static Expression abs(@NonNull Expression operand)
      Creates an ABS(expr) function that returns the absolute value of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The ABS(expr) function.

    • acos

      @NonNull public static Expression acos(@NonNull Expression operand)
      Creates an ACOS(expr) function that returns the inverse cosine of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The ACOS(expr) function.

    • asin

      @NonNull public static Expression asin(@NonNull Expression operand)
      Creates an ASIN(expr) function that returns the inverse sin of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The ASIN(expr) function.

    • atan

      @NonNull public static Expression atan(@NonNull Expression operand)
      Creates an ATAN(expr) function that returns the inverse tangent of the numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The ATAN(expr) function.

    • atan2

      @NonNull public static Expression atan2(@NonNull Expression y, @NonNull Expression x)
      Returns the angle theta from the conversion of rectangular coordinates (x, y) to polar coordinates (r, theta).
      Parameters:
      x - the abscissa coordinate
      y - the ordinate coordinate
      Returns:
      the theta component of the point (r, theta) in polar coordinates that corresponds to the point (x, y) in Cartesian coordinates.

    • ceil

      @NonNull public static Expression ceil(@NonNull Expression operand)
      Creates a CEIL(expr) function that returns the ceiling value of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The CEIL(expr) function.

    • cos

      @NonNull public static Expression cos(@NonNull Expression operand)
      Creates a COS(expr) function that returns the cosine of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The COS(expr) function.

    • degrees

      @NonNull public static Expression degrees(@NonNull Expression operand)
      Creates a DEGREES(expr) function that returns the degrees value of the given radiants value expression.
      Parameters:
      operand - The expression.
      Returns:
      The DEGREES(expr) function.

    • e

      @NonNull public static Expression e()
      Creates a E() function that return the value of the mathematical constant 'e'.
      Returns:
      The E() constant function.

    • exp

      @NonNull public static Expression exp(@NonNull Expression operand)
      Creates a EXP(expr) function that returns the value of 'e' power by the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The EXP(expr) function.

    • floor

      @NonNull public static Expression floor(@NonNull Expression operand)
      Creates a FLOOR(expr) function that returns the floor value of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The FLOOR(expr) function.

    • ln

      @NonNull public static Expression ln(@NonNull Expression operand)
      Creates a LN(expr) function that returns the natural log of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The LN(expr) function.

    • log

      @NonNull public static Expression log(@NonNull Expression operand)
      Creates a LOG(expr) function that returns the base 10 log of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The LOG(expr) function.

    • pi

      @NonNull public static Expression pi()
      Creates a PI() function that returns the mathematical constant Pi.
      Returns:
      The PI() constant function.

    • power

      @NonNull public static Expression power(@NonNull Expression base, @NonNull Expression exp)
      Creates a POWER(base, exponent) function that returns the value of the given base expression power the given exponent expression.
      Parameters:
      base - The base expression.
      exp - The exponent expression.
      Returns:
      The POWER(base, exponent) function.

    • radians

      @NonNull public static Expression radians(@NonNull Expression operand)
      Creates a RADIANS(expr) function that returns the radians value of the given degrees value expression.
      Parameters:
      operand - The expression.
      Returns:
      The RADIANS(expr) function.

    • round

      @NonNull public static Expression round(@NonNull Expression operand)
      Creates a ROUND(expr) function that returns the rounded value of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The ROUND(expr) function.

    • round

      @NonNull public static Expression round(@NonNull Expression operand, @NonNull Expression digits)
      Creates a ROUND(expr, digits) function that returns the rounded value to the given number of digits of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      digits - The number of digits.
      Returns:
      The ROUND(expr, digits) function.

    • sign

      @NonNull public static Expression sign(@NonNull Expression operand)
      Creates a SIGN(expr) function that returns the sign (1: positive, -1: negative, 0: zero) of the given numeric expression.
      Parameters:
      operand - The expression.
      Returns:
      The SIGN(expr) function.

    • sin

      @NonNull public static Expression sin(@NonNull Expression operand)
      Creates a SIN(expr) function that returns the sin of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      Returns:
      The SIN(expr) function.

    • sqrt

      @NonNull public static Expression sqrt(@NonNull Expression operand)
      Creates a SQRT(expr) function that returns the square root of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      Returns:
      The SQRT(expr) function.

    • tan

      @NonNull public static Expression tan(@NonNull Expression operand)
      Creates a TAN(expr) function that returns the tangent of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      Returns:
      The TAN(expr) function.

    • trunc

      @NonNull public static Expression trunc(@NonNull Expression operand)
      Creates a TRUNC(expr) function that truncates all of the digits after the decimal place of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      Returns:
      The trunc function.

    • trunc

      @NonNull public static Expression trunc(@NonNull Expression operand, @NonNull Expression digits)
      Creates a TRUNC(expr, digits) function that truncates the number of the digits after the decimal place of the given numeric expression.
      Parameters:
      operand - The numeric expression.
      digits - The number of digits to truncate.
      Returns:
      The TRUNC(expr, digits) function.

    • contains

      @NonNull public static Expression contains(@NonNull Expression operand, @NonNull Expression substring)
      Creates a CONTAINS(expr, substr) function that evaluates whether the given string expression conatins the given substring expression or not.
      Parameters:
      operand - The string expression.
      substring - The substring expression.
      Returns:
      The CONTAINS(expr, substr) function.

    • length

      @NonNull public static Expression length(@NonNull Expression operand)
      Creates a LENGTH(expr) function that returns the length of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The LENGTH(expr) function.

    • lower

      @NonNull public static Expression lower(@NonNull Expression operand)
      Creates a LOWER(expr) function that returns the lowercase string of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The LOWER(expr) function.

    • ltrim

      @NonNull public static Expression ltrim(@NonNull Expression operand)
      Creates a LTRIM(expr) function that removes the whitespace from the beginning of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The LTRIM(expr) function.

    • rtrim

      @NonNull public static Expression rtrim(@NonNull Expression operand)
      Creates a RTRIM(expr) function that removes the whitespace from the end of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The RTRIM(expr) function.

    • trim

      @NonNull public static Expression trim(@NonNull Expression operand)
      Creates a TRIM(expr) function that removes the whitespace from the beginning and the end of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The TRIM(expr) function.

    • upper

      @NonNull public static Expression upper(@NonNull Expression operand)
      Creates a UPPER(expr) function that returns the uppercase string of the given string expression.
      Parameters:
      operand - The string expression.
      Returns:
      The UPPER(expr) function.

    • millisToString

      @NonNull public static Expression millisToString(@NonNull Expression operand)
      Creates a MILLIS_TO_STR(expr) function that will convert a numeric input representing milliseconds since the Unix epoch into a full ISO8601 date and time string in the device local time zone.
      Parameters:
      operand - The string expression.
      Returns:
      The MILLIS_TO_STR(expr) function.

    • millisToUTC

      @NonNull public static Expression millisToUTC(@NonNull Expression operand)
      Creates a MILLIS_TO_UTC(expr) function that will convert a numeric input representing milliseconds since the Unix epoch into a full ISO8601 date and time string in UTC time.
      Parameters:
      operand - The string expression.
      Returns:
      The MILLIS_TO_UTC(expr) function.

    • stringToMillis

      @NonNull public static Expression stringToMillis(@NonNull Expression operand)
      Creates a STR_TO_MILLIS(expr) that will convert an ISO8601 datetime string into the number of milliseconds since the unix epoch. Valid date strings must start with a date in the form YYYY-MM-DD (time only strings are not supported).

      Times can be of the form HH:MM, HH:MM:SS, or HH:MM:SS.FFF. Leading zero is not optional (i.e. 02 is ok, 2 is not). Hours are in 24-hour format. FFF represents milliseconds, and *trailing* zeros are optional (i.e. 5 == 500).

      Time zones can be in one of three forms: (+/-)HH:MM (+/-)HHMM Z (which represents UTC)

      Parameters:
      operand - The string expression.
      Returns:
      The STR_TO_MILLIS(expr) function.

    • stringToUTC

      @NonNull public static Expression stringToUTC(@NonNull Expression operand)
      Creates a STR_TO_UTC(expr) that will convert an ISO8601 datetime string into a full ISO8601 UTC datetime string. Valid date strings must start with a date in the form YYYY-MM-DD (time only strings are not supported).

      Times can be of the form HH:MM, HH:MM:SS, or HH:MM:SS.FFF. Leading zero is not optional (i.e. 02 is ok, 2 is not). Hours are in 24-hour format. FFF represents milliseconds, and *trailing* zeros are optional (i.e. 5 == 500).

      Time zones can be in one of three forms: (+/-)HH:MM (+/-)HHMM Z (which represents UTC)

      Parameters:
      operand - The string expression.
      Returns:
      The STR_TO_UTC(expr) function.