org.apache.derby.diag

Class StatementDuration

java.lang.Object

org.apache.derby.vti.VTITemplate

org.apache.derby.diag.StatementDuration

All Implemented Interfaces:

java.lang.AutoCloseable, java.sql.ResultSet, java.sql.Wrapper, AwareVTI

public class StatementDuration
extends VTITemplate

StatementDuration is a virtual table which can be used to analyze the execution duration of the statements of "interest" in db2j.log or a specified file when db2j.language.logStatementText=true.

A limitation is that, for each transaction ID, a row will not be returned for the last statement with that transaction id. (Transaction IDs change within a connection after a commit or rollback, if the transaction that just ended modified data.)

The execution duration is the time between the beginning of execution of two successive statements. There are a number of reasons why this time may not be accurate. The duration could include time spent in the application waiting for user input, doing other work, etc. It may also only include a portion of the actual execution time, if the application executes a new statement before draining the previous open ResultSet. StatementDuration can be used to get a rough sense of where the bottlenecks in an application's JDBC code are.

The StatementDuration virtual table has the following columns:

• TS varchar(26) - not nullable. The timestamp of the statement.
• THREADID varchar(80) - not nullable. The thread name.
• XID varchar(15) - not nullable. The transaction ID.
• LOGTEXT long varchar - nullable. Text of the statement or commit or rollback.
• DURATION varchar(10) - not nullable. Duration, in milliseconds, of the statement.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.derby.vti.VTITemplate

VTITemplate.ColumnDescriptor

Field Summary

Fields inherited from interface java.sql.ResultSet

CLOSE_CURSORS_AT_COMMIT, CONCUR_READ_ONLY, CONCUR_UPDATABLE, FETCH_FORWARD, FETCH_REVERSE, FETCH_UNKNOWN, HOLD_CURSORS_OVER_COMMIT, TYPE_FORWARD_ONLY, TYPE_SCROLL_INSENSITIVE, TYPE_SCROLL_SENSITIVE

Constructor Summary

Constructors

Constructor and Description
StatementDuration() StatementDuration() accesses the error log in derby.system.home, if set, otherwise it looks in the current directory.
StatementDuration(java.lang.String inputFileName)

Method Summary

Modifier and Type	Method and Description
void	close()
java.sql.ResultSetMetaData	getMetaData()
java.lang.String	getString(int columnNumber) All columns in StatementDuration VTI have String data types.
boolean	next()
boolean	wasNull()

Methods inherited from class org.apache.derby.vti.VTITemplate

absolute, afterLast, beforeFirst, cancelRowUpdates, clearWarnings, deleteRow, findColumn, first, getArray, getArray, getAsciiStream, getAsciiStream, getBigDecimal, getBigDecimal, getBigDecimal, getBigDecimal, getBinaryStream, getBinaryStream, getBlob, getBlob, getBoolean, getBoolean, getByte, getByte, getBytes, getBytes, getCharacterStream, getCharacterStream, getClob, getClob, getConcurrency, getContext, getCursorName, getDate, getDate, getDate, getDate, getDouble, getDouble, getFetchDirection, getFetchSize, getFloat, getFloat, getHoldability, getInt, getInt, getLong, getLong, getNCharacterStream, getNCharacterStream, getNClob, getNClob, getNString, getNString, getObject, getObject, getObject, getObject, getObject, getObject, getRef, getRef, getReturnTableSignature, getRow, getRowId, getRowId, getShort, getShort, getSQLXML, getSQLXML, getStatement, getString, getTime, getTime, getTime, getTime, getTimestamp, getTimestamp, getTimestamp, getTimestamp, getType, getUnicodeStream, getUnicodeStream, getURL, getURL, getWarnings, insertRow, isAfterLast, isBeforeFirst, isClosed, isFirst, isLast, isWrapperFor, last, moveToCurrentRow, moveToInsertRow, previous, refreshRow, relative, rowDeleted, rowInserted, rowUpdated, setContext, setFetchDirection, setFetchSize, unwrap, updateArray, updateArray, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateAsciiStream, updateBigDecimal, updateBigDecimal, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBinaryStream, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBlob, updateBoolean, updateBoolean, updateByte, updateByte, updateBytes, updateBytes, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateCharacterStream, updateClob, updateClob, updateClob, updateClob, updateClob, updateClob, updateDate, updateDate, updateDouble, updateDouble, updateFloat, updateFloat, updateInt, updateInt, updateLong, updateLong, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNCharacterStream, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNClob, updateNString, updateNString, updateNull, updateNull, updateObject, updateObject, updateObject, updateObject, updateRef, updateRef, updateRow, updateRowId, updateRowId, updateShort, updateShort, updateSQLXML, updateSQLXML, updateString, updateString, updateTime, updateTime, updateTimestamp, updateTimestamp

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.sql.ResultSet

updateObject, updateObject, updateObject, updateObject

Constructor Detail

StatementDuration

public StatementDuration()
                  throws StandardException

StatementDuration() accesses the error log in derby.system.home, if set, otherwise it looks in the current directory. StatementDuration('filename') will access the specified file name.

Throws:

StandardException

StatementDuration

public StatementDuration(java.lang.String inputFileName)
                  throws StandardException

Throws:

StandardException

Method Detail

getMetaData

public java.sql.ResultSetMetaData getMetaData()

Specified by:

getMetaData in interface java.sql.ResultSet

Overrides:

getMetaData in class VTITemplate

See Also:

ResultSet.getMetaData()

next

public boolean next()
             throws java.sql.SQLException

Throws:

java.sql.SQLException - If database access error occurs.

See Also:

ResultSet.next()

close

public void close()

See Also:

ResultSet.close()

getString

public java.lang.String getString(int columnNumber)
                           throws java.sql.SQLException

All columns in StatementDuration VTI have String data types.

Specified by:

getString in interface java.sql.ResultSet

Overrides:

getString in class VTITemplate

Throws:

java.sql.SQLException - If database access error occurs.

See Also:

ResultSet.getString(int)

wasNull

public boolean wasNull()

Specified by:

wasNull in interface java.sql.ResultSet

Overrides:

wasNull in class VTITemplate

See Also:

ResultSet.wasNull()