[AliRana30]

Key Changes

• SqlIdentifierUtils: Added a utility in wayang-basic to strictly validate single-part and multipart table/column identifiers using regex patterns (^[a-zA-Z_][a-zA-Z0-9_$]*(?:\.[a-zA-Z_][a-zA-Z0-9_$]*)*$) and escape/quote identifiers according to database dialect.
• TableSink: Integrated validation in the constructor and setter so any invalid or malicious table/column identifier is rejected early with an IllegalArgumentException.
• JdbcTableSinkOperator & JdbcExecutor: Quoted table names in generated DROP TABLE IF EXISTS, CREATE TABLE ... AS, and INSERT INTO clauses. Multipart identifiers (such as Trino catalog.schema.table) are quoted segment-by-segment ("catalog"."schema"."table").
• JavaTableSink & SparkTableSink: Updated to use SqlIdentifierUtils for safe identifier quoting.
• Unit Tests: Added SqlIdentifierUtilsTest and updated JdbcTableSinkExecutorTest to assert proper quoting and rejection of SQL injection payloads.

Fixes : #836.

Verification

• SqlIdentifierUtilsTest (10 tests passed)
• JdbcTableSinkExecutorTest (8 tests passed)
• JavaTableSinkTest (7 tests passed)
• SparkTableSinkTest (10 tests passed)
• apache-rat:check (0 unapproved licenses)

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[AliRana30]

@zkaoudi PR is up for your review.

[novatechflow]

Thanks for the contribution. Pls always add regression tests.

• Quoting changes identifier case handling. On HSQLDB, an existing unquoted target_append becomes TARGET_APPEND, but the new SQL targets "target_append". Append fails, and overwrite leaves the original table untouched.
• The shared validation rejects valid BigQuery names such as my-project.sales.orders, including the documented backtick-quoted form.

Reproduced both with focused Java 17 checks. Preserve identifier lookup semantics & handle dialect-specific names.

[AliRana30]

@novatechflow I have addressed both issues and added regression tests covering both case folding and BigQuery formats. Verified on Java 17