[PHOENIX-5752] Phoenix RVC InListExpression generates wrong DESC order column scan

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Resolved
• Labels: DESC
• Assignee: Xinyi Yan
• Reporter: Xinyi Yan
• Created: 28/Feb/20 02:54
• Updated: 09/Jun/20 02:46
• Resolved: 09/Jun/20 02:46

Description

@Test
public void testInListExpressionWithDescOrderWithRightQueryPlan() throws Exception {
    String fullTableName = generateUniqueName();
    String fullViewName = generateUniqueName();
    String tenantView = generateUniqueName();
    String TENANT_SPECIFIC_URL1 = getUrl() + ';' + TENANT_ID_ATTRIB + "=tenant1";

    try (Connection conn = DriverManager.getConnection(getUrl())) {
        conn.setAutoCommit(true);
        try (Statement stmt = conn.createStatement()) {
            stmt.execute("CREATE TABLE " + fullTableName + "(\n" + " TENANT_ID CHAR(15) NOT NULL,\n" + " KEY_PREFIX CHAR(3) NOT NULL,\n" +
                    " CONSTRAINT PK PRIMARY KEY (\n" + " TENANT_ID," + " KEY_PREFIX" + ")) MULTI_TENANT=TRUE");
            stmt.execute("CREATE VIEW " + fullViewName + "(\n" + " ID1 VARCHAR NOT NULL,\n" + " ID2 VARCHAR NOT NULL,\n" + " ID3 BIGINT, ID4 BIGINT \n" +
                    " CONSTRAINT PKVIEW PRIMARY KEY\n" + " (\n" + " ID1, ID2 DESC\n" + ")) " +
                    "AS SELECT * FROM " + fullTableName + " WHERE KEY_PREFIX = '0CY'");
        }
    }

    try (Connection viewConn = DriverManager.getConnection(TENANT_SPECIFIC_URL1)) {
        viewConn.setAutoCommit(true);
        try (Statement stmt = viewConn.createStatement()) {
            stmt.execute("CREATE VIEW IF NOT EXISTS " + tenantView + " AS SELECT * FROM " + fullViewName);

            try (PreparedStatement preparedStmt = viewConn.prepareStatement(
                    "SELECT * FROM " + tenantView + " WHERE (ID1, ID2) " +
                            "IN (('me', '000000000000500')," +
                            "('bar', '000000000000400')," +
                            "('foo', '000000000000300'))")) {
                QueryPlan queryPlan = PhoenixRuntime.getOptimizedQueryPlan(preparedStmt);
                assertTrue(queryPlan.getExplainPlan().toString().contains("POINT LOOKUP ON "));
            }
        }
    }
}

InListExpression generates a range scan instead of a point lookup. This might result in an extremely bad performance for the DELETE and SELECT query. From my perspective, it might be the point that we need to refactor and/or rewrite query optimization code so that we don't need to have two code paths for InListExpresson. We can simply do the query rewrite to ((ID1=? AND ID2=?) or (ID1=? AND  ID2=?)) as the right approach.