# Token Functions for Attribute Expressions

The token functions in this section are used in the attribute expressions in the destination clause of a `LOAD` statement.

Function Output type Description

gsql_reverse(in_string)

`STRING`

Returns a string with the characters in the reverse order of the input string in_string.

gsql_concat(string1, string2,…​,stringN)

`STRING`

Returns a string which is the concatenation of all the input strings.

gsql_uuid_v4()

`STRING`

Returns a version-4 UUID.

gsql_split_by_space(in_string)

`STRING`

Returns a modified version of in_string, in which each space character is replaced with ASCII 30 (decimal).

gsql_substring(str, beginIndex [, length])

`STRING`

Returns the substring beginning at beginIndex, having the given length.

gsql_find(str, substr)

`INT`

Returns the start index of the substring within the string. If it is not found, then return -1.

gsql_length(str)

`INT`

Returns the length of the string.

gsql_replace(str, oldToken, newToken [, max])

`STRING`

Returns the string resulting from replacing all matching substrings of oldToken with newToken in the original string. If a max count is provided, there can only be up to that many replacements.

gsql_regex_replace(str, regex, replaceSubstr)

`STRING`

Returns the string resulting from replacing all substrings in the input string that match the given regex token with the substitute string.

gsql_regex_match(str, regex)

bool

Returns true if the given string token matches the given regex token and false otherwise.

gsql_to_bool(in_string)

bool

Returns true if the in_string is either "t" or "true", with case-insensitive checking. Returns false otherwise.

gsql_to_uint(in_string)

`UINT`

• If in_string is the string representation of an unsigned integer, the function returns that integer.

• If in_string is the string representation of a non-negative float, the function returns that number cast as an integer.

gsql_to_int(in_string)

`INT`

• If in_string is the string representation of an integer, the function returns that integer.

• If in_string is the string representation of a float, the function returns that number cast as an integer.

gsql_ts_to_epoch_seconds(timestamp)

`UINT`

Converts a timestamp in canonical string format to Unix epoch time, which is the int number of seconds since Jan. 1, 1970. Refer to the timestamp input format note below.

gsql_current_time_epoch(0)

`UINT`

Returns the current time in Unix epoch seconds. By convention, the input parameter should be 0, but it is ignored.

flatten (column_to_be_split, group_separator, 1)

flatten (column_to_be_split, group_separator, sub_field_separator, number_of_sub_fields_in_one_group)

Splits a multi-value field into a set of records. Those records are first stored in a temporary table, and then the temporary table can be loaded into vertices and/or edges.

flatten_json_array ($"array_name") flatten_json_array ($"array_name", $"sub_obj_1",$"sub_obj_2", …​, \$"sub_obj_n")

Parses a JSON array of primitive values or JSON objects, as well as JSON objects in a column of a CSV file.

split(column_to_be_split, element_separator)

split(column_to_be_split, key_value_separator, element _separator)

Reads a compound token and splits it into a collection of elements, to form a set or list collection, or a map.

gsql_upper(in_string)

`STRING`

Returns the input string in upper-case.

gsql_lower(in_string)

`STRING`

Returns the input string in lower-case.

gsql_trim(in_string)

`STRING`

Trims whitespace from the beginning and end of the input string.

gsql_ltrim(in_string)

gsql_rtrim(in_string)

`STRING`

Trims white space from either the beginning or the end of the input string (Left or right).

gsql_year(timestamp)

`INT`

Returns 4-digit year from timestamp.

gsql_month(timestamp)

`INT`

Returns month (1-12) from timestamp.

gsql_day(timestamp)

`INT`

Returns day (1-31) from timestamp.

gsql_year_epoch(epoch)

`INT`

Returns 4-digit year from Unix epoch time, which is the number of seconds since Jan. 1, 1970.

gsql_month_epoch(epoch)

`INT`

Returns month (1-12) from Unix epoch time, which is the number of seconds since Jan. 1, 1970.

gsql_day_epoch(epoch)

`INT`

Returns day (1-31) from Unix epoch time, which is the number of seconds since Jan. 1, 1970.