feat: adds format, regex_extract function and more type tests

[killme2008]

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Refer to a related PR or issue link (optional)

#1168

What's changed and what's your intention?

Main changes:

• Migrated type and related function tests from DuckDB.
• Implemented format(fmt, arg1, arg2...) and regex_extract functions.
• Added Date64 support for date_format.

Remaining issues:

1. DataFusion does not correctly support sampling: Support data source sampling with TABLESAMPLE apache/datafusion#13563
2. Subqueries are not supported, for example:

SELECT a, b,
    a - (SELECT MIN(a) FROM test WHERE a IS NOT NULL) AS diff_from_min
FROM test
WHERE a IS NOT NULL
ORDER BY a - (SELECT MIN(a) FROM test WHERE a IS NOT NULL);

Error: 1001 (Unsupported), This feature is not implemented: Physical plan does not support logical expression ScalarSubquery(<subquery>)

TODO:

• Contribute format(fmt, arg1, arg2...) and regex_extract functions to Datafusion and remove our custom implementations.

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[killme2008]

It's known issue.

[Copilot]

Pull Request Overview

This PR adds enhanced string function support and comprehensive type testing to GreptimeDB. The primary purpose is to implement the FORMAT function with escape character support, the REGEXP_EXTRACT function for regex-based text extraction, and expand test coverage for various data types including Unicode strings, floating-point edge cases, and SQL operations.

Key Changes:

• Implementation of FORMAT and REGEXP_EXTRACT string functions with proper escaping and regex support
• Addition of comprehensive test suites for string functions, Unicode handling, NaN/infinity arithmetic, and SQL operations
• Upgrade of regex dependency to version 1.12 for improved functionality

Reviewed Changes

Copilot reviewed 53 out of 54 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/common/function/src/scalars/string/*	New string function implementations including format and regex_extract
tests/cases/standalone/common/function/string/*	Comprehensive string function test suites
tests/cases/standalone/common/types/float/*	Floating-point type tests covering NaN, infinity, and IEEE compliance
tests/cases/standalone/common/types/string/*	Unicode and large string handling tests
tests/cases/standalone/common/order/*	ORDER BY functionality tests
tests/cases/standalone/common/sample/*	Table sampling tests
Cargo.toml and related	Regex dependency upgrade to version 1.12

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[evenyag]

What if the positional value has the same value as the needed_names? We may not be able to distinguish that because the needed_names only contains the name, without the position of the format name.

[killme2008]

Good catch! We should require the name parameter to appear at the end of the parameter list, similar to Python or Rust macros.

Let me fix it.

[killme2008]

@evenyag I removed the format function for now, as it’s not the right time to add it before we consider it carefully. Let’s remove it temporarily.

PTAL.