13、多字段条件查询和修改

　　表A中的字段有actno, cnlno,bal,pwd;表B中的字段为Actno，Cnlno，TxnAmt;目的是将A表中的bal修改为B表中的TxnAmt，命令：

　　DB2 "update A set bal=(select txnamt from B where actno=A.actno and cnlno=A.Cnlno) where A.actno||A.cnlno in (select Actno||cnlno from B );

　　14、多条件匹配查询

　　查询某个表中条件是B?AAA的记录：

　　DB2 "select * from A where actno like "B_AAA%"".

　　查询数据中存在某些字符的记录：

　　DB2 "select * from A where actno like "%-AAA%".

　　15、数据库恢复的处理

　　进行数据库恢复的时候使用以下的命令：

 restore db db1 to /tstdb2/catalog into db newlogpath /tstdb2/db2log buffer 2048
replace existing redirect parallelism 16;
set tablespace containers for 1 using (path '/tstdb2/db2tmp');
set tablespace containers for 2 using
(device '/dev/rtstcontlv00' 2621440, device '/dev/rtstcontlv01' 2621440,
device '/dev/rtstcontlv02' 2621440, device '/dev/rtstcontlv03' 2621440 ) ;
restore db db1 continue;

　　恢复完成以后执行命令DB2s时报如下的错误：

P570:>db2s
SQL1117N A connection to or activation of database "DB" cannot be made
because of ROLL-FORWARD PENDING. SQLSTATE=57019
DB21034E The command was processed as an SQL statement because it was not a
valid Command Line Processor command. During SQL processing it returned:
SQL1024N A database connection does not exist. SQLSTATE=08003

　　解决办法如下：

P570:>db2 rollforward db db to end of logs and complete
Rollforward Status
Input database alias = db
Number of nodes have returned status = 1
Node number = 0
Rollforward status = not pending
Next log file to be read =
Log files processed = -
Last committed transaction = 2005-11-20-10.59.23.000000
DB20000I The ROLLFORWARD command completed successfully.