ackelcn created DERBY-7081:
------------------------------
Summary: A rotten comment in DataDictionaryImpl.java
Key: DERBY-7081
URL: https://issues.apache.org/jira/browse/DERBY-7081
Project: Derby
Issue Type: Bug
Reporter: ackelcn
When I read the code of DataDictionaryImpl.java, I found a comment:
{code:java}
private String genColumnReferenceSQL(private String genColumnReferenceSQL(
TableDescriptor td, String colName, String tabName, boolean isOldTable, int
colPositionInRuntimeResultSet ) throws StandardException
{
ColumnDescriptor colDesc = null;
if ((colDesc = td.getColumnDescriptor(colName)) == null)
{
throw StandardException.newException(SQLState.LANG_COLUMN_NOT_FOUND,
tabName+"."+colName);
}
/* ** Generate something like this: **
** CAST (org.apache.derby.iapi.db.Factory::
** getTriggerExecutionContext().getNewRow().
** getObject(<colPosition>) AS DECIMAL(6,2))
**
** Column position is used to avoid the wrong column being
** selected problem (DERBY-1258) caused by the case insensitive
** JDBC rules for fetching a column by name.
...
}{code}
The comment mentions DERBY-1258. I found that DERBY-1258 modified
CreateTriggerNode.java, and the patch is as follows:
{code:java}
@@ -587,7 +587,11 @@@@ -587,7 +587,11 @@
**
** cast (org.apache.derby.iapi.db.Factory::
** getTriggerExecutionContext().getNewRow().
- ** getObject('<colName>') AS DECIMAL(6,2))
+ ** getObject(<colPosition>) AS DECIMAL(6,2))
+ **
+ ** Column position is used to avoid the wrong column being
+ ** selected problem (DERBY-1258) caused by the case insensitive
+ ** JDBC rules for fetching a column by name.
**
** The cast back to the SQL Domain may seem redundant
** but we need it to make the column reference appear
@@ -599,9 +603,11 @@
** CREATE TRIGGER ... INSERT INTO T length(Column), ...
*/ StringBuffer methodCall = new StringBuffer();
- methodCall.append("cast
(org.apache.derby.iapi.db.Factory::getTriggerExecutionContext().");
+ methodCall.append("CAST
(org.apache.derby.iapi.db.Factory::getTriggerExecutionContext().");
methodCall.append(isOldTable ? "getOldRow()" : "getNewRow()");
- methodCall.append(".getObject('"+colName+"') AS ");
+ methodCall.append(".getObject(");
+ methodCall.append(colDesc.getPosition());
+ methodCall.append(") AS "); DataTypeDescriptor dts =
colDesc.getType(); TypeId typeId = dts.getTypeId();
@@ -611,8 +617,9 @@
** case.
*/ methodCall.append(
- (typeId.userType() ? typeId.getSQLTypeName() : dts.getSQLstring())
- + ") ");
+ (typeId.userType() ? typeId.getSQLTypeName() : dts.getSQLstring()));
+
+ methodCall.append(") "); return methodCall.toString(); }
{code}
The patch modified the genColumnReferenceSQL method. However, the method does
not appear in the latest version of CreateTriggerNode.java. I found that
DERBY-4874 deleted the whole method.
I am wondering whether DataDictionaryImpl.java mentions a rotten issue report
(DERBY-1258), in that all the modifications of this issue do not appear in the
latest version.
Would you please check the problem? If it is, the reference of DERBY-1258 shall
be removed from the comment of DataDictionaryImpl.java.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
