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- to_byte(target_arg)
- DESCRIPTION:
Function converts a numeric data type to the Vantage byte representation
(byte value) of the input value.
PARAMETERS:
target_arg:
Required Argument.
Specifies a ColumnExpression of an numeric column or a numeric literal value.
If target_arg is NULL, the function returns NULL.
Format of a ColumnExpression of a column: '<dataframe>.<dataframe_column>.expression'.
Supported SQL column types: BYTEINT, SMALLINT, INTEGER, and BIGINT
The size of the byte string returned varies according to the data type of the
target_arg input argument as shown below:
==================================================
| IF target_arg type is | THEN the result type is |
==================================================
| BYTEINT | BYTE(1) |
| SMALLINT | BYTE(2) |
| INTEGER | BYTE(4) |
| BIGINT | BYTE(8) |
===================================================
NOTE:
Function accepts positional arguments only.
EXAMPLES:
# Load the data to run the example.
>>> load_example_data("dataframe", "bytes_table")
>>>
# Create a DataFrame on 'bytes_table' table.
>>> bytes_table = DataFrame("bytes_table")
>>> bytes_table
byte_col varbyte_col blob_col
id_col
2 b'61' b'616263643132' b'6162636431323233'
1 b'62' b'62717765' b'3331363136323633'
0 b'63' b'627A7863' b'3330363136323633'
>>>
# Example converts values in "id_col" to bytes.
# Import func from sqlalchemy to execute to_byte function.
>>> from sqlalchemy import func
# Create a sqlalchemy Function object.
# Note: Function name case does not matter. We can use the function name in
# lower case, upper case or mixed case.
>>> bit_byte_func_ = func.to_byte(bytes_table.id_col.expression)
>>>
# Pass the Function object as input to DataFrame.assign().
>>> df = bytes_table.assign(id_col_to_byte_=bit_byte_func_)
>>> print(df)
byte_col varbyte_col blob_col id_col_to_byte_
id_col
2 b'61' b'616263643132' b'6162636431323233' b'2'
1 b'62' b'62717765' b'3331363136323633' b'1'
0 b'63' b'627A7863' b'3330363136323633' b'0'
>>>
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