…ssions in PostgreSQL/mysql/oracle/sqlserver, and fix the null pointer issue in the regular expression
#9209

Purpose of this pull request

added contents about multiple tables and regular expressions in PostgreSQL/mysql/oracle/sqlserver, and fix the null pointer issue in the regular expression.

Does this PR introduce any user-facing change?

Yes.
This PR enhances the table_list parameter to directly support regex patterns for table filtering, while maintaining backward compatibility.
Here's the detailed breakdown:

New Feature: Direct Use of Regular Expressions in table_path
Purpose: Allow users to write regular expressions directly in the table_path field within table_list to filter tables.
Example Configuration:
"table_list"=[
{
"table_path"="TEST.TEST_DB_*" # Matches all tables with the "TEST_DB" prefix
}
]
This configuration matches all tables prefixed with TEST_DB (e.g., TEST_DB_2023, TEST_DB_2024).

Improvement and Fix:
Enhanced the robustness of the approximateRowCntStatement method in OracleDialect.
Fixed a null pointer error in Oracle when executing queries with empty or invalid parameters.
Key Notes:
The table_path now supports regex syntax (e.g., TEST.TEST_DB_* → matches all tables under the TEST schema with names starting with TEST_DB_).
The Oracle fix ensures stable execution of row count estimation logic, avoiding crashes due to unhandled edge cases.

How was this patch tested?

Testing Environment
OS: Linux (Ubuntu 20.04)
SeaTunnel Version: 2.3.9
Execution Mode: Flink on YARN (yarn-application)
Databases:
PostgreSQL 16.0(Source)
Iceberg (Sink)

Test Configuration:
Created a configuration file pg2iceberg.conf to read tables matching the regex TEST.TEST_DB_* from PostgreSQL:
{
env {
execution.parallelism = 1
job.mode = "BATCH"
job.name = "seatunnel_batch_job"
}

source配置
source {
JDBC {
url = "jdbc:postgresql://xxxxxxx:xxxxx/xxxxx"
driver = "org.postgresql.Driver"
user = "xxxxxxxx"
password = "xxxxxxx"
"table_list" = [
{
"table_path" = "postgres.public.test_db_2.*"
}
]
split.size = 5000
fetch_size = 2000
}
}

sink配置
sink {
Iceberg {
........
}
}
}

Execution Command:
./bin/start-seatunnel-flink-15-connector-v2.sh --config pg2iceberg.conf --deploy-mode run-application --target yarn-application --name multitable_pg2Iceberg

Check log：
Filtering tables with regex pattern: postgres.public.test_db_2.*
Found regex match table: postgres.public.test_db_20
Found regex match table: postgres.public.test_db_21
Found regex match table: postgres.public.test_db_22
Found regex match table: postgres.public.test_db_20250324
Found regex match table: postgres.public.test_db_202502
Found regex match table: postgres.public.test_db_202501
Total tables matched after filtering: 6

Check list

• If any new Jar binary package adding in your PR, please add License Notice according
  New License Guide
• [ * ] If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs
• [ * ] If you are contributing the connector code, please check that the following files are updated:
  1. Update plugin-mapping.properties and add new connector information in it
  2. Update the pom file of seatunnel-dist
  3. Add ci label in label-scope-conf
  4. Add e2e testcase in seatunnel-e2e
  5. Update connector plugin_config