apache / shardingsphere

Empowering Data Intelligence with Distributed SQL for Sharding, Scalability, and Security Across All Databases.
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Support parsing Oracle MERGE USING sql #27154

Open FlyingZC opened 1 year ago

FlyingZC commented 1 year ago

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:

MERGE USING Product_Changes S     -- Source/Delta table
INTO Products D1                  -- Destination table 1
ON (D1.PROD_ID = S.PROD_ID)       -- Search/Join condition
WHEN MATCHED THEN UPDATE          -- update if join
SET D1.PROD_STATUS = S.PROD_NEW_STATUS
MODEL PARTITION BY (country) DIMENSION BY (product, time)
  MEASURES (sale sales, 0 mavg)
  RULES UPDATE
  (mavg[product IN ('Bounce', 'Y Box', 'Mouse Pad'), ANY] =
   AVG(sales)[CV(product), time BETWEEN CV(time) 
   AND CV(time) - 2])
MODEL PARTITION BY (country) DIMENSION BY (year) MEASURES (sales)
  (sales[year=2001] = AVG(sales)[year BETWEEN 1990 AND 2000]
NOAUDIT ALL ON DEFAULT;
NOAUDIT ALL ON emp;

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
github-actions[bot] commented 1 year ago

There hasn't been any activity on this issue recently, and in order to prioritize active issues, it will be marked as stale.

github-actions[bot] commented 1 year ago

There hasn't been any activity on this issue recently, and in order to prioritize active issues, it will be marked as stale.