/****************************************************************************
** (c) Copyright IBM Corp. 2007 All rights reserved.
**
** The following sample of source code ("Sample") is owned by International
** Business Machines Corporation or one of its subsidiaries ("IBM") and is
** copyrighted and licensed, not sold. You may use, copy, modify, and
** distribute the Sample in any form without payment to IBM, for the purpose of
** assisting you in the development of your applications.
**
** The Sample code is provided to you on an "AS IS" basis, without warranty of
** any kind. IBM HEREBY EXPRESSLY DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR
** IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Some jurisdictions do
** not allow for the exclusion or limitation of implied warranties, so the above
** limitations or exclusions may not apply to you. IBM shall not be liable for
** any damages you suffer as a result of using, copying, modifying or
** distributing the Sample, even if IBM has been advised of the possibility of
** such damages.
*****************************************************************************
**
** SOURCE FILE NAME: dblognoconn.sqc
**
** SAMPLE: How to read the database logs with no database connection
**
** Archive logging needs to be enabled to read database logs when there is
** no connection to the database. The database logs are archived and read
** from the archive location.
**
** PREREQUISITES : Update the db cfg parameter to enable archive logging :
**
** db2 UPDATE DB CFG FOR SAMPLE USING LOGARCHMETH1 DISK:<archive log path>
** <archive log path> : path with write permission where the
** database logs can be archived
** db2 TERMINATE
** db2 BACKUP DB SAMPLE
**
** Note : You must be disconnected from the sample database to run this
** program. To ensure you are, enter 'db2 CONNECT RESET' on the
** command line prior to running the sample.
**
** EXECUTION : dblognoconn <db name> <nodename> <username> <pswd>
**
** Note : Perform 'db2 RESET DB CFG FOR SAMPLE' after running the sample
**
** DB2 APIs USED:
** db2CfgGet -- Get db configuration parameters
** db2ArchiveLog -- Archive the active log files
** db2ReadLogNoConn -- Read the database logs without a db connection
** db2ReadLogNoConnInit -- Initialize reading the database logs
** without a db connection
** db2ReadLogNoConnTerm -- Terminate reading the database logs
** without a db connection
**
**
*****************************************************************************
**
** For detailed information about database backup and database recovery, see
** the Data Recovery and High Availability Guide and Reference. This manual
** will help you to determine which database and table space recovery methods
** are best suited to your business environment.
**
** For more information on the sample programs, see the README file.
**
** For information on developing C applications, see the Application
** Development Guide.
**
** For information on using SQL statements, see the SQL Reference.
**
** For information on DB2 APIs, see the Administrative API Reference.
**
** For the latest information on programming, building, and running DB2
** applications, visit the DB2 Information Center:
** http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/index.jsp
****************************************************************************/
#include "utilrecov.c"
#include "utilemb.h"
/* local function prototypes */
int DbReadLogRecordsNoConn(char *, char *, char *, char *, char *);
int main(int argc, char *argv[])
{
int rc = 0;
char nodeName[SQL_INSTNAME_SZ + 1] = { 0 };
char serverWorkingPath[SQL_PATH_SZ + 1] = { 0 };
char dbAlias[SQL_ALIAS_SZ + 1] = { 0 };
char user[USERID_SZ + 1] = { 0 };
char pswd[PSWD_SZ + 1] = { 0 };
/* check the command line arguments */
rc = CmdLineArgsCheck3(argc, argv, dbAlias, nodeName, user, pswd);
CHECKRC(rc, "CmdLineArgsCheck3");
printf("\nTHIS SAMPLE SHOWS HOW TO READ DATABASE LOGS ASYNCHRONOUSLY\n");
printf("WITH NO DATABASE CONNECTION.\n");
/* attach to a local or remote instance */
rc = InstanceAttach(nodeName, user, pswd);
CHECKRC(rc, "Instance Attach");
/* get the server working path */
rc = ServerWorkingPathGet(dbAlias, serverWorkingPath);
CHECKRC(rc, "ServerWorkingPathGet");
/* call the routine to prune the history files */
rc = DbRecoveryHistoryFilePrune(dbAlias, user, pswd);
CHECKRC(rc, "DbRecoveryHistoryFilePrune");
/* call the routine to read the log records for no db connection */
rc = DbReadLogRecordsNoConn(dbAlias, nodeName, user, pswd, serverWorkingPath);
CHECKRC(rc, "DbReadLogRecordsNoConn");
return 0;
} /* end main */
int DbReadLogRecordsNoConn(char dbAlias[],
char nodeName[],
char user[],
char pswd[],
char serverWorkingPath[])
{
int rc = 0;
struct sqlca sqlca = { 0 };
char logPath[SQL_PATH_SZ + 1] = { 0 };
db2CfgParam cfgParameters[1] = { 0 };
db2Cfg cfgStruct = { 0 };
char nodeNum[] = "NODE0000\0";
db2Uint32 readLogMemSize = 0;
char *readLogMemory = NULL;
struct db2ArchiveLogStruct archiveLogInput = { 0 };
struct db2ReadLogNoConnInitStruct readLogInit = { 0 };
struct db2ReadLogNoConnInfoStruct readLogInfo = { 0 };
struct db2ReadLogNoConnStruct readLogInput = { 0 };
db2LSN startLSN;
db2LSN endLSN;
char *logBuffer = NULL;
db2Uint32 logBufferSize = 0;
struct db2ReadLogNoConnTermStruct readLogTerm = { 0 };
printf("\n*********************************\n");
printf("*** NO DB CONNECTION READ LOG ***\n");
printf("*********************************\n");
printf("\nUSE THE DB2 APIs:\n");
printf(" db2ArchiveLog -- Archive the active log files\n");
printf(" db2ReadLogNoConnInit -- Initialize reading the database ");
printf("logs without a db connection\n");
printf(" db2ReadLogNoConn -- Read the database logs without a db connection\n");
printf(" db2ReadLogNoConnTerm -- Terminate reading the database logs ");
printf("without a db connection\n");
printf("TO READ LOG RECORDS FROM THE ARCHIVED LOG DIRECTORY.\n");
/* Determine the logpath to read log files from */
cfgParameters[0].flags = 0;
cfgParameters[0].token = SQLF_DBTN_LOGARCHMETH1;
cfgParameters[0].ptrvalue =
(char *)malloc((SQL_PATH_SZ + 1) * sizeof(char));
/* Initialize cfgStruct */
cfgStruct.numItems = 1;
cfgStruct.paramArray = cfgParameters;
cfgStruct.flags = db2CfgDatabase;
cfgStruct.dbname = dbAlias;
db2CfgGet(db2Version970, (void *)&cfgStruct, &sqlca);
DB2_API_CHECK("log path -- get");
strcpy(logPath, cfgParameters[0].ptrvalue + 5);
strcat(logPath, nodeName);
strcat(logPath, "/SAMPLE/NODE0000/C0000000/");
free(cfgParameters[0].ptrvalue);
cfgParameters[0].ptrvalue = NULL;
/* connect to the database */
rc = DbConn(dbAlias, user, pswd);
CHECKRC(rc, "DbConn");
/* Invoke the SQL statements to fill the database log */
printf("\n Invoke the following SQL statements:\n");
printf(" ALTER TABLE emp_resume DATA CAPTURE CHANGES;\n");
printf(" COMMIT;\n");
printf(" INSERT INTO emp_resume\n");
printf(" VALUES('000120', 'ascii', 'This is a new resume.');\n");
printf(" ('000030', 'ascii', 'This is another new resume');\n");
printf(" COMMIT;\n");
printf(" DELETE FROM emp_resume WHERE empno = '000120';\n");
printf(" DELETE FROM emp_resume WHERE empno = '000030';\n");
printf(" COMMIT;\n");
printf(" DELETE FROM emp_resume WHERE empno = '000140';\n");
printf(" ROLLBACK;\n");
printf(" ALTER TABLE emp_resume DATA CAPTURE NONE;\n");
printf(" COMMIT;\n");
EXEC SQL ALTER TABLE emp_resume DATA CAPTURE CHANGES;
EMB_SQL_CHECK("SQL statement 1 -- invoke");
EXEC SQL COMMIT;
EMB_SQL_CHECK("SQL statement 2 -- invoke");
EXEC SQL INSERT INTO emp_resume
VALUES('000120', 'ascii', 'This is a new resume.'),
('000030', 'ascii', 'This is another new resume');
EMB_SQL_CHECK("SQL statement 3 -- invoke");
EXEC SQL COMMIT;
EMB_SQL_CHECK("SQL statement 4 -- invoke");
EXEC SQL DELETE FROM emp_resume WHERE empno = '000120';
EMB_SQL_CHECK("SQL statement 5 -- invoke");
EXEC SQL DELETE FROM emp_resume WHERE empno = '000030';
EMB_SQL_CHECK("SQL statement 6 -- invoke");
EXEC SQL COMMIT;
EMB_SQL_CHECK("SQL statement 7 -- invoke");
EXEC SQL DELETE FROM emp_resume WHERE empno = '000140';
EMB_SQL_CHECK("SQL statement 8 -- invoke");
EXEC SQL ROLLBACK;
EMB_SQL_CHECK("SQL statement 9 -- invoke");
EXEC SQL ALTER TABLE emp_resume DATA CAPTURE NONE;
EMB_SQL_CHECK("SQL statement 10 -- invoke");
EXEC SQL COMMIT;
EMB_SQL_CHECK("SQL statement 11 -- invoke");
/* Disconnect from the database */
rc = DbDisconn(dbAlias);
CHECKRC(rc, "DbDisconn");
/* Detach from the local or remote instance before reading log information */
rc = InstanceDetach(nodeName);
CHECKRC(rc, "InstanceDetach");
/* Invoke the db2ArchiveLog API to archive the active logs */
archiveLogInput.piDatabaseAlias = dbAlias;
archiveLogInput.piUserName = user;
archiveLogInput.piPassword = pswd;
archiveLogInput.iAllNodeFlag = (int)NULL;
archiveLogInput.iNumNodes = (int)NULL;
archiveLogInput.piNodeList = NULL;
archiveLogInput.iOptions = (int)NULL;
db2ArchiveLog(db2Version970, &archiveLogInput, &sqlca);
if (sqlca.sqlcode != 0)
{
DB2_API_CHECK("database archive -- archive logs");
}
/* Allocate memory for the API's control blocks and log
* buffer */
readLogMemSize = 16 * 4096;
readLogMemory = (char *)malloc(readLogMemSize);
/* Invoke the initialization API to set up the control blocks */
readLogInit.iFilterOption = DB2READLOG_FILTER_ON;
readLogInit.piLogFilePath = logPath;
readLogInit.piOverflowLogPath = NULL;
readLogInit.iRetrieveLogs = DB2READLOG_RETRIEVE_OFF;
readLogInit.piDatabaseName = dbAlias;
readLogInit.piNodeName = nodeNum;
readLogInit.iReadLogMemoryLimit = readLogMemSize;
readLogInit.poReadLogMemPtr = &readLogMemory;
db2ReadLogNoConnInit(db2Version970, &readLogInit, &sqlca);
if (sqlca.sqlcode != SQLU_RLOG_LSNS_REUSED)
{
DB2_API_CHECK("database logs no db conn -- initialization");
}
/* Invoke the db2ReadLogNoConn API to query the current log information */
readLogInput.iCallerAction = DB2READLOG_QUERY;
readLogInput.piStartLSN = NULL;
readLogInput.piEndLSN = NULL;
readLogInput.poLogBuffer = NULL;
readLogInput.iLogBufferSize = 0;
readLogInput.piReadLogMemPtr = readLogMemory;
readLogInput.poReadLogInfo = &readLogInfo;
db2ReadLogNoConn(db2Version970, &readLogInput, &sqlca);
if (sqlca.sqlcode != 0)
{
DB2_API_CHECK("database logs no db conn -- query");
}
/* Read some log records */
logBufferSize = 64 * 1024; /* Maximum size of a log buffer */
logBuffer = (char *)malloc(logBufferSize);
memcpy(&startLSN, &(readLogInfo.nextStartLSN), sizeof(startLSN));
endLSN.lsnU64 = 0xffffffffffffffff;
readLogInput.iCallerAction = DB2READLOG_READ;
readLogInput.piStartLSN = &startLSN;
readLogInput.piEndLSN = &endLSN;
readLogInput.poLogBuffer = logBuffer;
readLogInput.iLogBufferSize = logBufferSize;
readLogInput.piReadLogMemPtr = readLogMemory;
readLogInput.poReadLogInfo = &readLogInfo;
db2ReadLogNoConn(db2Version970, &readLogInput, &sqlca);
if (sqlca.sqlcode != SQLU_RLOG_READ_TO_CURRENT)
{
DB2_API_CHECK("database logs no db conn -- read");
}
else
{
if (readLogInfo.logRecsWritten == 0)
{
printf("\n Database log empty.\n");
}
}
/* Display the log records */
rc = LogBufferDisplay(logBuffer, readLogInfo.logRecsWritten, 0);
CHECKRC(rc, "LogBufferDisplay");
while (sqlca.sqlcode != SQLU_RLOG_READ_TO_CURRENT)
{
/* read the next log sequence */
memcpy(&startLSN, &(readLogInfo.nextStartLSN), sizeof(startLSN));
/* Extract a log record and read the next log sequence asynchronously */
db2ReadLogNoConn(db2Version970, &readLogInput, &sqlca);
if (sqlca.sqlcode != SQLU_RLOG_READ_TO_CURRENT)
{
DB2_API_CHECK("database logs no db conn -- read");
}
/* display log buffer */
rc = LogBufferDisplay(logBuffer, readLogInfo.logRecsWritten, 0);
CHECKRC(rc, "LogBufferDisplay");
}
printf("\nRead to end of logs.\n\n");
free(logBuffer);
logBuffer = NULL;
logBufferSize = 0;
/* Invoke the db2ReadLogNoConnTerm API to terminate reading the logs */
readLogTerm.poReadLogMemPtr = &readLogMemory;
db2ReadLogNoConnTerm(db2Version970, &readLogTerm, &sqlca);
DB2_API_CHECK("database logs no db conn -- terminate");
return 0;
} /* DbReadLogRecordsNoConn */