Substring

Supported in: Batch, Streaming

Extract substring.

Expression categories: Numeric

Declared arguments

• Expression - no description
  Expression<String>
• Start - The index to start substring from (inclusive). Negative numbers start from end of string. This is 1-indexed.
  Expression<Integer>
• optional Length - The length of the substring to extract. If not provided the remainder of the string is extracted.
  Expression<Integer>

Output type: String

Examples

Example 1: Base case

Argument values:

• Expression: string
• Start: start
• Length: length

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Example 2: Base case

Description: When no length is provided, the substring runs to end of string. Argument values:

• Expression: string
• Start: start
• Length: null

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Example 3: Null case

Description: In case of nulls, the output is always null. Argument values:

• Expression: string
• Start: start
• Length: length

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Example 4: Edge case

Description: When length is longer than remaining sub string, the output is the sub string until the end of the string. Argument values:

• Expression: string
• Start: start
• Length: length

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