> I cant figure out how the generated byte code classes get hooked up with
these calls
I don't think this particular call stack is very much
concerned with generated byte code classes.
At this point in the processing of the SELECT query,
the execution engine is associating the logical tablenames
from your query with the physical files that hold the
actual data.
So if the query is:
select e.id,d.name from employees e, departments d
where e.dept_id = d.id
then what we're doing in the stack trace that you posted
is to translate the 'employees' table into something like
c:\temp\db\seg0\c2e1.dat
and translate the 'departments' table into something like
c:\temp\db\seg0\c3b1.dat
and then we open those files and let the storage subsystem
do its initialization to be ready to read from those tables.
This process is called "binding" the tables, so that's why
you see the word "bind" in many of those method names.
thanks,
bryan
On 8/18/2013 8:04 AM, Madushanka Fonseka wrote:
Hi,
I have been working on Apache derby in order to make it an option to query
vague data (using fuzzy models) not only crisp data.
This is the progress I made so far.
* Stdied Apache architecture, its modules : Query Parser, Excution, Store, JDBC
Layer etc.
* Prep a fuzzy query grammar file
* Studied Apache derby byte code generation machinery
I figured out the call hierarchy that happens on a "SELECT" query.
at org.apache.derby.impl.store.raw.xact.Xact.setActiveState(Xact.java:1864)
at org.apache.derby.impl.store.raw.xact.Xact.openContainer(Xact.java:1342)
at
org.apache.derby.impl.store.access.conglomerate.OpenConglomerate.init(OpenConglomerate.java:910)
at org.apache.derby.impl.store.access.heap.Heap.open(Heap.java:688)
at
org.apache.derby.impl.store.access.RAMTransaction.openConglomerate(RAMTransaction.java:464)
at
org.apache.derby.impl.store.access.RAMTransaction.openConglomerate(RAMTransaction.java:1287)
at
org.apache.derby.impl.sql.catalog.DataDictionaryImpl.getDescriptorViaIndexMinion(DataDictionaryImpl.java:9470)
at
org.apache.derby.impl.sql.catalog.DataDictionaryImpl.getDescriptorViaIndex(DataDictionaryImpl.java:9426)
at
org.apache.derby.impl.sql.catalog.DataDictionaryImpl.locateSchemaRow(DataDictionaryImpl.java:1817)
at
org.apache.derby.impl.sql.catalog.DataDictionaryImpl.getSchemaDescriptor(DataDictionaryImpl.java:1684)
at
org.apache.derby.iapi.sql.StatementUtil.getSchemaDescriptor(StatementUtil.java:138)
*at
org.apache.derby.impl.sql.compile.QueryTreeNode.getSchemaDescriptor(QueryTreeNode.java:1066)*
*at
org.apache.derby.impl.sql.compile.QueryTreeNode.getSchemaDescriptor(QueryTreeNode.java:1042)*
*at
org.apache.derby.impl.sql.compile.FromBaseTable.bindTableDescriptor(FromBaseTable.java:2673)*
*at
org.apache.derby.impl.sql.compile.FromBaseTable.bindNonVTITables(FromBaseTable.java:2303)*
*at org.apache.derby.impl.sql.compile.FromList.bindTables(FromList.java:344)*
*at
org.apache.derby.impl.sql.compile.SelectNode.bindNonVTITables(SelectNode.java:524)*
*at
org.apache.derby.impl.sql.compile.DMLStatementNode.bindTables(DMLStatementNode.java:193)*
*at
org.apache.derby.impl.sql.compile.DMLStatementNode.bind(DMLStatementNode.java:127)*
*at
org.apache.derby.impl.sql.compile.CursorNode.bindStatement(CursorNode.java:274)*
*at
org.apache.derby.impl.sql.GenericStatement.prepMinion(GenericStatement.java:423)*
*at
org.apache.derby.impl.sql.GenericStatement.prepare(GenericStatement.java:100)*
*at
org.apache.derby.impl.sql.conn.GenericLanguageConnectionContext.prepareInternalStatement(GenericLanguageConnectionContext.java:1109)*
*at org.apache.derby.impl.jdbc.EmbedStatement.execute(EmbedStatement.java:685)*
*at
org.apache.derby.impl.jdbc.EmbedStatement.executeQuery(EmbedStatement.java:148)*
*at edu.uom.derby.test.Main.go(Main.java:218)*
I know the machinery up to the bold method calls in the listing. I cant figure
out how the generated byte code classes get hooked up with these calls along
with resultset and excution factories. I would be much pleased if you could
help me.
Madushanka Fonseka
Sn. Engineer - technology
