Teradata Package for Python Function Reference | 20.00 - array_join - Teradata Package for Python - Look here for syntax, methods and examples for the functions included in the Teradata Package for Python.
Teradata® Package for Python Function Reference - 20.00
- Deployment
- VantageCloud
- VantageCore
- Edition
- VMware
- Enterprise
- IntelliFlex
- Product
- Teradata Package for Python
- Release Number
- 20.00.00.11
- Published
- August 2026
- ft:locale
- en-US
- ft:lastEdition
- 2026-08-13
- dita:id
- TeradataPython_FxRef_Enterprise_2000
- Product Category
- Teradata Vantage
- teradataml.dataframe.sql.DataFrameColumn.array_join = array_join(self, delimiter=',', null_replacement=None, varchar_length=1024)
- DESCRIPTION:
Join array elements into a string using the specified delimiter.
PARAMETERS:
delimiter:
Optional Argument.
Specifies the delimiter to use when joining the array elements.
Default Value: ','
Types: str
null_replacement:
Optional Argument.
Specifies the string to use in place of NULL elements in the array.
Note:
* If not specified, NULL elements are skipped in the joined string.
Types: str
varchar_length:
Optional Argument.
Specifies the length of the resulting VARCHAR string.
Default Value: 1024
Types: int
RETURNS:
ColumnExpression
EXAMPLES:
>>> from teradataml import *
>>> load_example_data("array", "array_table")
# Create a DataFrame on 'array_table'.
>>> df = DataFrame("array_table")
>>> df
arr1 arr2 arr3
id
1 (10,20,30,40,50) (23,200,215,40,21) ('ab','bc','cd','ab','ef')
4 (180,28,38,48,58) (30,NULL,NULL,250,27) ('mn','no',NULL,'op','pq')
2 (150,25,35,45,55) (28,50,95,90,26) ('xy','yz','za','ab','xy')
6 (16,261,36,46,56) (29,170,160,46,25) ('uv','xy','ab','xy','yz')
3 (12,22,320,42,52) (25,22,140,200,23) ('pq','ab','ab','st','tu')
5 (14,24,34,44,54) (26,NULL,NULL,180,24) ('ij','jk',NULL,'kl','lm')
# Example 1: Join elements of array column 'arr3' with default delimiter '*'.
>>> res = df.assign(joined_arr = df.arr3.array_join(delimiter='*'))
>>> res
arr1 arr2 arr3 joined_arr
id
5 (14,24,34,44,54) (26,NULL,NULL,180,24) ('ij','jk',NULL,'kl','lm') ij*jk*kl*lm
2 (150,25,35,45,55) (28,50,95,90,26) ('xy','yz','za','ab','xy') xy*yz*za*ab*xy
6 (16,261,36,46,56) (29,170,160,46,25) ('uv','xy','ab','xy','yz') uv*xy*ab*xy*yz
1 (10,20,30,40,50) (23,200,215,40,21) ('ab','bc','cd','ab','ef') ab*bc*cd*ab*ef
3 (12,22,320,42,52) (25,22,140,200,23) ('pq','ab','ab','st','tu') pq*ab*ab*st*tu
4 (180,28,38,48,58) (30,NULL,NULL,250,27) ('mn','no',NULL,'op','pq') mn*no*op*pq
# Example 2: Join elements of array column 'arr2' with delimiter '-' and
# replace NULL elements with 'NA'.
>>> res = df.assign(joined_arr = df.arr2.array_join(delimiter='-', null_replacement='NA'))
>>> res
arr1 arr2 arr3 joined_arr
id
2 (150,25,35,45,55) (28,50,95,90,26) ('xy','yz','za','ab','xy') 28-50-95-90-26
6 (16,261,36,46,56) (29,170,160,46,25) ('uv','xy','ab','xy','yz') 29-170-160-46-25
3 (12,22,320,42,52) (25,22,140,200,23) ('pq','ab','ab','st','tu') 25-22-140-200-23
4 (180,28,38,48,58) (30,NULL,NULL,250,27) ('mn','no',NULL,'op','pq') 30-NA-NA-250-27
1 (10,20,30,40,50) (23,200,215,40,21) ('ab','bc','cd','ab','ef') 23-200-215-40-21
5 (14,24,34,44,54) (26,NULL,NULL,180,24) ('ij','jk',NULL,'kl','lm') 26-NA-NA-180-24
# Example 3: Join elements of array column 'temp_arr' with default delimiter ',' where elements
# in source array contains same delimiter.
>>> from teradatasqlalchemy.types import ARRAY_VARCHAR
>>> sdf = df.assign(temp_arr=Array(("Hi, world", "This is a test, "), atype=ARRAY_VARCHAR('[3]')))
>>> res = sdf.assign(joined_arr = sdf.temp_arr.array_join())
>>> res
arr1 arr2 arr3 temp_arr joined_arr
id
5 (14,24,34,44,54) (26,NULL,NULL,180,24) ('ij','jk',NULL,'kl','lm') ('Hi, world','This is a test, ') Hi, world,This is a test,
2 (150,25,35,45,55) (28,50,95,90,26) ('xy','yz','za','ab','xy') ('Hi, world','This is a test, ') Hi, world,This is a test,
3 (12,22,320,42,52) (25,22,140,200,23) ('pq','ab','ab','st','tu') ('Hi, world','This is a test, ') Hi, world,This is a test,
1 (10,20,30,40,50) (23,200,215,40,21) ('ab','bc','cd','ab','ef') ('Hi, world','This is a test, ') Hi, world,This is a test,
4 (180,28,38,48,58) (30,NULL,NULL,250,27) ('mn','no',NULL,'op','pq') ('Hi, world','This is a test, ') Hi, world,This is a test,
6 (16,261,36,46,56) (29,170,160,46,25) ('uv','xy','ab','xy','yz') ('Hi, world','This is a test, ') Hi, world,This is a test,