Github user twdsilva commented on a diff in the pull request:
https://github.com/apache/phoenix/pull/303#discussion_r191948821
--- Diff: phoenix-core/src/it/java/org/apache/phoenix/end2end/ViewIT.java
---
@@ -388,51 +435,65 @@ public void
testViewAndTableInDifferentSchemas(boolean isNamespaceMapped) throws
} catch (TableNotFoundException ignore) {
}
ddl = "DROP TABLE " + fullTableName1;
- validateCannotDropTableWithChildViewsWithoutCascade(conn,
fullTableName1);
ddl = "DROP VIEW " + fullViewName2;
conn.createStatement().execute(ddl);
ddl = "DROP TABLE " + fullTableName1;
conn.createStatement().execute(ddl);
}
-
+
@Test
- public void testDisallowDropOfColumnOnParentTable() throws Exception {
+ public void testDropOfColumnOnParentTableInvalidatesView() throws
Exception {
Connection conn = DriverManager.getConnection(getUrl());
+ String fullTableName = generateUniqueTableName();
+ String viewName = generateUniqueViewName();
+ splitSystemCatalog(Lists.newArrayList(fullTableName, viewName));
+
String ddl = "CREATE TABLE " + fullTableName + " (k1 INTEGER NOT
NULL, k2 INTEGER NOT NULL, v1 DECIMAL, CONSTRAINT pk PRIMARY KEY (k1, k2))" +
tableDDLOptions;
conn.createStatement().execute(ddl);
- String viewName = "V_" + generateUniqueName();
ddl = "CREATE VIEW " + viewName + "(v2 VARCHAR, v3 VARCHAR) AS
SELECT * FROM " + fullTableName + " WHERE v1 = 1.0";
conn.createStatement().execute(ddl);
- try {
- conn.createStatement().execute("ALTER TABLE " + fullTableName
+ " DROP COLUMN v1");
- fail();
- } catch (SQLException e) {
-
assertEquals(SQLExceptionCode.CANNOT_MUTATE_TABLE.getErrorCode(),
e.getErrorCode());
+ conn.createStatement().execute("ALTER TABLE " + fullTableName + "
DROP COLUMN v1");
+ // TODO see if its possibel to prevent the dropping of a column
thats required by a child view (for its view where clause)
+ // the view should be invalid
--- End diff --
I was thinking of handling the race condition by writing a cell using
checkAndPut with the column name being mutated (added or dropped) to the header
row of the base table. When a view is create the columns used in the view where
clause will also do a checkAndPut on this cell in the base table. If this is
happening concurrently only of the clients will succeed (either the drop
column, or the view creation).
If a DROP TABLE cascade is issued then the base table (with child views) is
dropped. When any child views are resolved and we see the base table does not
exists we throw a TableNotFoundException. If the DROP VIEW is issued without
CASCADE and there are child views the statement fails with a not allowed to
mutate exception. If a drop table without cascade and a create view happens
concurrently we could create the view even though the base table would have
been dropped, but the next time the view is resolved you would get a
TableNotFoundException.
---
