This is an automated email from the ASF dual-hosted git repository.
alamb pushed a commit to branch main
in repository https://gitbox.apache.org/repos/asf/arrow-datafusion.git
The following commit(s) were added to refs/heads/main by this push:
new 4569939b38 Minor: add examples for `arrow_cast` and `arrow_typeof` to
user guide (#7615)
4569939b38 is described below
commit 4569939b3850a74eb8daa0225ebf6390f99c6422
Author: Andrew Lamb <[email protected]>
AuthorDate: Fri Sep 22 08:30:58 2023 -0400
Minor: add examples for `arrow_cast` and `arrow_typeof` to user guide
(#7615)
* Minor: add examples for `arrow_cast` and `arrow_typeof`
* prettier
* Update docs/source/user-guide/sql/scalar_functions.md
Co-authored-by: Liang-Chi Hsieh <[email protected]>
---------
Co-authored-by: Liang-Chi Hsieh <[email protected]>
---
docs/source/user-guide/sql/scalar_functions.md | 34 +++++++++++++++++++++++---
1 file changed, 31 insertions(+), 3 deletions(-)
diff --git a/docs/source/user-guide/sql/scalar_functions.md
b/docs/source/user-guide/sql/scalar_functions.md
index b68cac5cb7..d5717b9c21 100644
--- a/docs/source/user-guide/sql/scalar_functions.md
+++ b/docs/source/user-guide/sql/scalar_functions.md
@@ -2566,12 +2566,28 @@ arrow_cast(expression, datatype)
- **expression**: Expression to cast.
Can be a constant, column, or function, and any combination of arithmetic or
string operators.
-- **datatype**: [Arrow data
type](https://arrow.apache.org/datafusion/user-guide/sql/data_types.html)
- to cast to.
+- **datatype**: [Arrow data
type](https://docs.rs/arrow/latest/arrow/datatypes/enum.DataType.html) name
+ to cast to, as a string. The format is the same as that returned by
[`arrow_typeof`]
+
+#### Example
+
+```
+❯ select arrow_cast(-5, 'Int8') as a,
+ arrow_cast('foo', 'Dictionary(Int32, Utf8)') as b,
+ arrow_cast('bar', 'LargeUtf8') as c,
+ arrow_cast('2023-01-02T12:53:02', 'Timestamp(Microsecond, Some("+08:00"))')
as d
+ ;
++----+-----+-----+---------------------------+
+| a | b | c | d |
++----+-----+-----+---------------------------+
+| -5 | foo | bar | 2023-01-02T12:53:02+08:00 |
++----+-----+-----+---------------------------+
+1 row in set. Query took 0.001 seconds.
+```
### `arrow_typeof`
-Returns the underlying Arrow data type of the expression:
+Returns the name of the underlying [Arrow data
type](https://docs.rs/arrow/latest/arrow/datatypes/enum.DataType.html) of the
expression:
```
arrow_typeof(expression)
@@ -2582,3 +2598,15 @@ arrow_typeof(expression)
- **expression**: Expression to evaluate.
Can be a constant, column, or function, and any combination of arithmetic or
string operators.
+
+#### Example
+
+```
+❯ select arrow_typeof('foo'), arrow_typeof(1);
++---------------------------+------------------------+
+| arrow_typeof(Utf8("foo")) | arrow_typeof(Int64(1)) |
++---------------------------+------------------------+
+| Utf8 | Int64 |
++---------------------------+------------------------+
+1 row in set. Query took 0.001 seconds.
+```
