FlyingZC opened a new issue, #27128:
URL: https://github.com/apache/shardingsphere/issues/27128

   # Background
   Hi community,
   This issue is for #26878.
   
   ShardingSphere parser engine helps users parse a SQL to get the AST 
(Abstract Syntax Tree) and visit this tree to get SQLStatement (Java Object). 
Currently, we are planning to enhance the support for Oracle SQL parsing in 
ShardingSphere.
   
   More details:
   
https://shardingsphere.apache.org/document/current/en/reference/sharding/parse/
   
   # Task
   This issue is to support more oracle sql parse, as follows:
   ```sql
   CREATE VIEW employees_manager AS 
       SELECT last_name, employee_id, manager_id FROM employees;
   ```
   
   ```sql
   CREATE VIEW sales_view AS
   SELECT country_name country, prod_name product, calendar_year year,
     SUM(amount_sold) sales, COUNT(amount_sold) cnt,
     MAX(calendar_year) KEEP (DENSE_RANK FIRST ORDER BY SUM(amount_sold) DESC)
     OVER (PARTITION BY country_name, prod_name) best_year,
     MAX(calendar_year) KEEP (DENSE_RANK LAST ORDER BY SUM(amount_sold) DESC)
     OVER (PARTITION BY country_name, prod_name) worst_year
   FROM sales, times, customers, countries, products
   WHERE sales.time_id = times.time_id AND sales.prod_id = products.prod_id AND
     sales.cust_id =customers.cust_id AND 
customers.country_id=countries.country_id
   GROUP BY country_name, prod_name, calendar_year;
   ```
   
   ```sql
   CREATE VIEW staff_dept_10 AS
   SELECT employee_id, last_name, job_id, 
          manager_id, department_id
   FROM   employees
   WHERE  department_id = 10
   WITH CHECK OPTION CONSTRAINT staff_dept_10_cnst;
   ```
   
   ```sql
   CREATE VIEW staff AS
     SELECT employee_id, last_name, job_id, manager_id, department_id
     FROM   employees;
   ```
   
   ```sql
   CREATE VIEW staff_dept_10_30 AS
   SELECT employee_id, last_name, job_id, e.department_id
   FROM   employees e, departments d
   WHERE  e.department_id IN (10, 30)
   AND    e.department_id = d.department_id;
   ```
   
   # Process
   1. First confirm that this is a correct oracle sql syntax, if not please 
ignore;
   2. Compare SQL definitions in Oficial SQL Doc and ShardingSphere SQL Doc;
   3. If there is any difference in ShardingSphere SQL Doc, please correct them 
by referring to the Official SQL Doc;
   4. Run mvn install the current_file_module;
   5. Check whether there are any exceptions. If indeed, please fix them. 
(Especially xxxVisitor.class);
   6. Add new corresponding SQL case in SQL Cases and expected parsed result in 
Expected Statment XML;
   7. Run SQLParserParameterizedTest to make sure no exceptions.
   
   # Relevant Skills
   1. Master JAVA language
   2. Have a basic understanding of Antlr `g4` file
   3. Be familiar with Oracle SQLs


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: 
[email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to