[feature](function) impl str_to_map (#49142)

[suxiaogang223]

Creates a map after splitting the input into key-value pairs using delimiters.

Syntax

str_to_map(expr [, pairDelim [, keyValueDelim] ] )

Arguments

expr: An STRING expression.
pairDelim: An optional STRING literal defaulting to ',' that specifies how to split entries.
keyValueDelim: An optional STRING literal defaulting to ':' that specifies how to split each key-value pair.
Returns

A MAP of STRING for both keys and values.

Both pairDelim and keyValueDelim are treated as regular expressions.

Examples

SQL

SELECT str_to_map('a:1,b:2,c:3', ',', ':');
{a -> 1, b -> 2, c -> 3}

SELECT str_to_map('a');
{a-> NULL}

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[Thearas]

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