Casting Functions
This topic describes the functions that are available for coercing data types in Graph Lakehouse.
- BNODE: Creates a blank node.
- DATATYPE: Returns the data type of the given value.
- DATETIME (or xsd:dateTime): Returns a dateTime value from the given string, long, or dateTime.
- DUR_TO_USECS: Casts a duration value to microseconds.
- ENCODE_FOR_URI: Encodes the specified string as a URI.
- FORMATDATETIME: Converts a value to a string in the specified dateTime format.
- FORMATDURATION: Converts a value into a string in the specified duration format.
- HEX: Converts a long value to a hexadecimal string.
- HEX2DEC: Converts a hexadecimal string to a long value.
- PARSEDATE: Attempts to convert the given string to a date, time, or dateTime value.
- RADIANS: Converts to radians an angle value that is in degrees.
- SERIALIZE: Creates a string representation of the input value.
- STR: Casts a value to a string.
- URI: Casts a string to a URI.
- USECS_TO_DUR: Converts a microseconds value to a duration.
- UUID: Generates a Universally Unique Identifier (UUID).
Typographical Conventions
The following list describes the conventions used to document function syntax:
CAPS: Although SPARQL is case-insensitive, SPARQL keywords in this section are written in uppercase for readability.[ argument ]: Brackets indicate an optional argument or keyword.|: Means OR. Indicates that you can use one or more of the specified options.
BNODE
This function creates a blank node.
Syntax
BNODE([ value ])
| value
|
string |
An optional string value from which to create the blank node. |
Returns
| blank node |
The generated blank node. |
DATATYPE
This function returns the data type of the given value.
Syntax
DATATYPE(value)
| value
|
any |
The value for which to return the data type. |
Returns
| data type URI |
The data type. |
DATETIME (or xsd:dateTime)
This function returns a dateTime value from the given long, double, date, or time value.
Syntax
DATETIME(value)
| value
|
long, double, date, time |
The value from which to return a dateTime. |
Returns
| dateTime |
The dateTime value. |
DUR_TO_USECS
This function calculates the time in microseconds from a duration value.
Syntax
DUR_TO_USECS(value)
| value
|
duration |
The duration value from which to calculate the time in microseconds. |
Returns
| long |
The number of microseconds. |
Example
SELECT (DUR_TO_USECS("PT2H11M48.376S"^^xsd:duration) as ?microseconds)
microseconds
------------------
7908376000
1 rows
ENCODE_FOR_URI
This function encodes the specified string as a URI and returns a string in URI format.
Syntax
ENCODE_FOR_URI(text)
| text
|
string |
The string value to encode as a URI. |
Returns
| string
|
The string as a URI. |
Example
PREFIX tickit: <http://anzograph.com/tickit/>
SELECT DISTINCT (ENCODE_FOR_URI(?eventname) as ?event)
FROM <http://anzograph.com/tickit>
WHERE {
?s tickit:eventid ?eventid .
?eventid tickit:eventname ?eventname .
}
ORDER BY ?event
LIMIT 10 event
-----------------------------------
.38%20Special
3%20Doors%20Down
70s%20Soul%20Jam
A%20Bronx%20Tale
A%20Catered%20Affair
A%20Chorus%20Line
A%20Christmas%20Carol
A%20Doll%27s%20House
A%20Man%20For%20All%20Seasons
A%20Midsummer%20Night%27s%20Dream
10 rows
HEX
This function converts a long value to a hexadecimal string.
Syntax
HEX(value)
| value
|
long |
The value to convert to a hexadecimal string. |
Returns
HEX2DEC
This function converts a hexadecimal string to a long value.
Syntax
HEX2DEC(value)
| value
|
string |
The hexadecimal string to convert. |
Returns
| long |
The converted value. |
FORMATDATETIME
This function converts a value into a string with the specified dateTime format.
Syntax
FORMATDATE(value, format)
| value
|
long, double, date, time, dateTime |
The value to convert to a string in the specified format. |
| format
|
string |
The format to use for the resulting dateTime string. Graph Lakehouse supports YYYY-MM-DDThh:mm:ss format. |
Returns
| string |
The dateTime as a string. |
FORMATDURATION
This function converts a value into a string with the specified duration format.
Syntax
FORMATDURATION(value, format)
| value
|
long, string, duration |
The value to convert to a string in the specified format. |
| format
|
string |
The format to use for the resulting duration string. Graph Lakehouse supports PnYnMnDTnHnMnS format. |
Returns
| string |
The duration as a string. |
PARSEDATE
This function attempts to convert the given string to a date, time, or dateTime value.
Syntax
PARSEDATE(value [, output_type ])
| value
|
string |
The string or plain literal value to convert to a date, time, or dateTime. |
| output_type
|
URI |
An optional URI (xsd:date, xsd:time, or xsd:dateTime) that specifies the type of value to return. If output_type is not specified, dateTime is returned. |
Returns
| date, time, or dateTime |
The conversion of the string to the desired type. |
RADIANS
This function converts to radians an angle value that is in degrees.
Syntax
RADIANS(angle)
| angle
|
double |
The angle value to convert to radians. |
Returns
| double |
The angle in radians. |
SERIALIZE
This function returns a string representation of the input value.
Syntax
SERIALIZE(value)
| value
|
any type except URI |
The value for which to generate a string representation. |
Returns
| string |
The string representation of the input value. |
STR
This function casts the specified value to a string.
Syntax
STR(value)
| value
|
any |
The value to convert to a string. |
Returns
| string |
The value as a string. |
URI
This function casts the specified string to a URI.
Syntax
URI(value)
| value
|
string |
The value to convert to a URI. |
Returns
USECS_TO_DUR
This function converts a number of microseconds in long, duration, or string format to a duration value.
Syntax
USECS_TO_DUR(value)
| value
|
long, duration, string |
The microseconds value to convert to a duration. |
Returns
| duration |
The input value as a duration. |
Example
SELECT (USECS_TO_DUR(76555373888) as ?duration)
duration
----------------------
PT21H15M55.373888S
1 rows
UUID
This function generates a Universally Unique Identifier (UUID).
Syntax
UUID()
Returns