Qshell
Did you know that the DB2 Qshell utility provides the capability to run SQL statements and scripts from Qshell (STRQSH)? Since V4R4, the DB2 utility has allowed you to execute SQL statements directly or from a file. In V5R1, the DB2 utility was enhanced to display the results of a SELECT statement on the screen via stdout. Here's the syntax for the DB2 utility: db2 [-tv] [-f file] sql-statement Options: - f file--Read the SQL statements from the specified file
- t--Use the semicolon as the statement termination character
- v--Echo the SQL statement to standard output
Here are some examples of how you can view the tables in a specific library or create database objects with the Qshell DB2 utility.
Code Example 1:
db2 "select table_name from qsys2.systables where table_schema='QSYS2' " Output:
PROCEDURES
QASQRESL
...
SYSTRIGGERS
SYSTRIGUPD
SYSTYPES
SYSVIEWDEP
SYSVIEWS
30 record(s) selected.
Code Example 2:
db2 -v -f mysqlfile.txt
Contents of mysqlfile.txt:
select table_name from qsys2.systables where table_schema='QSYS2';
create table qgpl.testtable (c1 integer); Output:
Executing: SELECT table_name FROM qsys2.systables where...
;
Done!
TABLE_NAME
---------------------------------------- PROCEDURES
...
SYSVIEWDEP
SYSVIEWS
Executing: CREATE TABLE qgpl.testtable(c1 integer);
**** CLI ERROR *****
SQLSTATE: 01567
Native Error Code: 7905
Table TESTTABLE in QGPL created but could not be journaled.
Done!
Perl Perl is another handy utility that can also benefit from DB2 access by using the DataBase Interface (DBI) and DataBase Driver (DBD) modules. The DBI is a database API module for Perl. This module defines a set of methods, variables, and conventions that provide a consistent interface to any database that has DBD defined. Perl has been available to iSeries users since V4R5. If you don't have Perl installed, click here for information about installing Perl on the iSeries. After installing PERL, you can find a DB2 access example in this file: /usr/local/lib/perl5/dbsamples/dbtest.pl To get you started, here's an example of a PERL script that again returns all of the table names in a library: use DBI;
use DBD::DB2::Constants;
use DBD::DB2;
# $DBI::dbi_debug = 9; # Turn on debug
$dbh = DBI->connect("dbi:DB2:*LOCAL") or die;
# $dbh->trace(3); # Turn on tracing
$stmt = "select table_name from qsys2.systables where table_schema='QSYS2' "
$sth = $dbh->prepare($stmt) or die "prepare got error " . $dbh->err;
$sth->execute() or die "execute got error" . $dbh->err;
$,=",";
$arr = $sth->fetchall_arrayref;
foreach $a (@$arr) {
foreach $ref (@$a) {
print "$ref "; }
print " ";
}
1; Output:
Qshell command line> perl dbtest.pl
PROCEDURES
QASQRESL
...
SYSTYPES
SYSVIEWDEP
SYSVIEWS
$ Additional information about Perl on iSeries can also be found in the "iSeries PERLs of Wisdom" white paper. Note: Neither PERL nor the DB2 utility are officially supported by IBM.
--Kent Milligan
kmill@us.ibm.com
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