BASE64DECODE Function
Converts an input base64 value to text. Output type is String.
base64 is a method of representing data in a binary format over text protocols. During encoding, text values are converted to binary values 0-63. Each value is stored as an ASCII character based on a conversion chart.
Typically, base64 is used to transmit binary information, such as images, over transfer methods that use text, such as HTTP.
注意
base64 is not an effective method of encryption.
For more information on base64, see https://en.wikipedia.org/wiki/Base64.
Wrangle vs. SQL: This function is part of Wrangle, a proprietary data transformation language. Wrangle is not SQL. For more information, see Wrangle Language.
Basic Usage
Column reference example:
base64decode(mySource)
Output: Decodes the base64 values from the mySource column into text.
String literal example:
base64decode('GVsbG8sIFdvcmxkLiA=')
Output:Decodes the input value to the following text: Hello, World..
Syntax and Arguments
base64decode(column_string)
Argument | Required? | Data Type | Description |
|---|---|---|---|
column_string | Y | string | Name of the column or string literal to be applied to the function |
For more information on syntax standards, see Language Documentation Syntax Notes.
column_string
Name of the column or string constant to be converted.
Missing string or column values generate missing string results.
String constants must be quoted (
'Hello, World').Multiple columns and wildcards are not supported.
Usage Notes:
Required? | Data Type | Example Value |
|---|---|---|
Yes | String literal or column reference | myColumn |
Examples
提示
For additional examples, see Common Tasks.
Example - base64 encoding and decoding
This example demonstrates how to convert an input string to a base64-encoded value and back to ASCII text strings.
Functions:
Item | Description |
|---|---|
BASE64ENCODE Function | Converts an input value to base64 encoding with optional padding with an equals sign ( |
BASE64DECODE Function | Converts an input base64 value to text. Output type is String. |
Source:
The following example contains three columns of different data types:
IntegerField | StringField | ssn |
|---|---|---|
-2082863942 | This is a test string. | 987654321 |
2012994989 | "Hello, world." | 987654322 |
-1637187918 | "Hello, world. Hello, world. Hello, world." | 987654323 |
-1144194035 | fyi | 987654324 |
-971872543 | 987654325 | |
353977583 | This is a test string. | 987-65-4321 |
-366583667 | "Hello, world." | 987-65-4322 |
-573117553 | "Hello, world. Hello, world. Hello, world." | 987-65-4323 |
2051041970 | fyi | 987-65-4324 |
522691086 | 987-65-4325 |
Transformation - encode:
You can use the following transformation to encode all of the columns in your dataset:
Transformation Name | |
|---|---|
Parameter: Columns | All |
Parameter: Formula | base64encode($col, true) |
Results - encode:
The transformed dataset now looks like the following. Note the padding (equals signs) at the end of some of the values. Padding is added by default.
IntegerField | StringField | ssn |
|---|---|---|
LTIwODI4NjM5NDI= | VGhpcyBpcyBhIHRlc3Qgc3RyaW5nLg== | OTg3NjU0MzIx |
MjAxMjk5NDk4OQ== | IkhlbGxvLCB3b3JsZC4i | OTg3NjU0MzIy |
LTE2MzcxODc5MTg= | IkhlbGxvLCB3b3JsZC4gSGVsbG8sIHdvcmxkLiBIZWxsbywgd29ybGQuIg== | OTg3NjU0MzIz |
LTExNDQxOTQwMzU= | Znlp | OTg3NjU0MzI0 |
LTk3MTg3MjU0Mw== | OTg3NjU0MzI1 | |
MzUzOTc3NTgz | VGhpcyBpcyBhIHRlc3Qgc3RyaW5nLg== | OTg3LTY1LTQzMjE= |
LTM2NjU4MzY2Nw== | IkhlbGxvLCB3b3JsZC4i | OTg3LTY1LTQzMjI= |
LTU3MzExNzU1Mw== | IkhlbGxvLCB3b3JsZC4gSGVsbG8sIHdvcmxkLiBIZWxsbywgd29ybGQuIg== | OTg3LTY1LTQzMjM= |
MjA1MTA0MTk3MA== | Znlp | OTg3LTY1LTQzMjQ= |
NTIyNjkxMDg2 | OTg3LTY1LTQzMjU= |
Transformation - decode:
The following transformation can be used to decode all of the columns:
Transformation Name | |
|---|---|
Parameter: Columns | All |
Parameter: Formula | base64decode($col) |
Results - decode:
IntegerField | StringField | ssn |
|---|---|---|
-2082863942 | This is a test string. | 987654321 |
2012994989 | "Hello, world." | 987654322 |
-1637187918 | "Hello, world. Hello, world. Hello, world." | 987654323 |
-1144194035 | fyi | 987654324 |
-971872543 | 987654325 | |
353977583 | This is a test string. | 987-65-4321 |
-366583667 | "Hello, world." | 987-65-4322 |
-573117553 | "Hello, world. Hello, world. Hello, world." | 987-65-4323 |
2051041970 | fyi | 987-65-4324 |
522691086 | 987-65-4325 |