Getting something is wrong with the execute statement. It just seems to hang forever when I run in command prompt. It doesn't die either. does execute maybe need parameters?
#!/usr/bin/perl
use DBI;
use Data::Dumper;
$dbh = DBI->connect('DB', 'NAME', 'PASS',{ LongReadLen => 1000000} ) or die 'Error: cant connect to db';
$st= "update table set the_id = 7 where mid = 23 and tid = 22";
my $UpdateRecord = $dbh->prepare($st) or die "Couldn't prepare statement: $st".$dbh->errstr;
$UpdateRecord->execute() or die "can not execute $UpdateRecord".$dbh->errstr;
$UpdateRecord->finish;
$dbh->disconnect();
EDIT:
I tried binding in execute as well as using bind_param(), and it's still hanging up.
you need a do instead of prepare.
my $UpdatedRecord = $dbh->do($st) or die "Statement fails: $st".$dbh->errstr;
From DBI:
This method is typically most useful for non-SELECT statements that
either cannot be prepared in advance (due to a limitation of the
driver) or do not need to be executed repeatedly. It should not be
used for SELECT statements because it does not return a statement
handle (so you can't fetch any data).
Also it's always better to add/use db driver module,the one you are using, at top after use DBI; statement.
use DBD::Oracle;
Also add
use strict;
use warnings;
Problem was that I locked a bunch of objects from failing to put the disconnect in before I ran it once...yeah, don't do that.
Related
I'm trying to execute SQL script that has lot of DML commands using Perl.
Basically there is some reference number which is required to be updated every time in SQL script before it executes, so I'm passing it as a parameter to Perl script which will further replace with parameter and execute. I'm doing this task in IntelliJ IDEA 2022.3.1 (Community Edition).
Problem: Unable to understand but Database connectivity is completely fine, and is fetching SQL script correctly, even replacement of reference number is also fine. But when trying to execute, it's not doing any changes in the Database. It looks like SQL commands are not really executing (as it is executing quickly which is not supposed to). I added warn with execute, so I got that warn message, but there is no error/exception message.
Please try to understand more details via code.
If anywhere I'm doing it wrong, please tell me. I have basic knowledge of Perl so might be doing it wrong. Can't provide more details about SQL script, it is confidential. But I can make sure that there is no error, as it is working fine if execute in it's dedicated tool. Thank you in advance!
#!/usr/bin/perl
use strict;
use warnings FATAL => 'all';
use DBI;
# Connect to the database
my $EnvDatabase = $ENV{"DATABASE"};
if (! defined $EnvDatabase) {
&ERROR ("The environment variable DATABASE is not defined");
exit (-1);
}
print "Updating in Database: $EnvDatabase\n" ;
my ($DBUser, $DBPass, $SID) = split (/\/|\#/,$EnvDatabase);
if (! (defined $DBUser && defined $DBPass && defined $SID )) {
&ERROR ('The environment variable DATABASE is not properly defined');
exit (-1);
}
my $dbh = DBI->connect( "dbi:Oracle:".$SID, $DBUser, $DBPass,{AutoCommit=>0,PrintError=>0})
|| &errorExit( "Unable to connect to database [$DBI::errstr] ");
# Get the input parameters
my $param1 = shift;
my $param2 = "###123###";
# Read the SQL file into a variable
my $sql = do {
local $/ = undef;
open my $fh, "<", "C:/someScript/someSampleSqlWithDMLCommands.sql" or die "could not open file: $!";
<$fh>;
};
# Replace with the parameter
$sql =~ s/$param2/$param1/g;
# Execute the SQL statements
$dbh->do($sql) || warn("Unable to execute ", $dbh->errstr);
$dbh->commit;
$dbh->disconnect;
OUTPUT: Updating in Database: database name declared in environment
Unable to execute ORA-00900: invalid SQL statement (DBD ERROR: OCIStmtExecute) at C:/**/autoScript.pl line 37.
Process finished with exit code 0
I have a shell script which calls some SQL like so
sqlplus system/$password#$instance #./oracle/mysqlfile.sql $var1 $var2 $var3
Then in mysqlfile.sql, I define properties like this:
DEFINE var1=&1
DEFINE var2=&3
DEFINE var3=&3
Later in the file, I call another SQL script:
// i wish to wrap this in a if statement - pseudo-code
if(var3="true") do the following
#./oracle/myOthersqlfile.sql &&varA &&varB
I am not sure how to implement this though, any suggestions appreciated
You could (ab)use substitution variables:
set termout off
column var3_path new_value var3_path
select case
when '&var3' = 'true' then './oracle/myOthersqlfile.sql &&varA &&varB'
else '/dev/null'
end as var3_path
from dual;
set termout on
#&var3_path
The query between the set termout commands - which just hide the output of the query - uses a case expression to pick either your real file path or a dummy file; I've used /dev/null, but you could have a 'no-op' file of your own that does nothing if that's clearer. The query gives the result of that the alias var3_path. The new_value line before it turns that into a substitution variable. The # then expands that variable.
So if var3 is 'true' then that runs:
#./oracle/myOthersqlfile.sql &&varA &&varB
(or, actually, with the varA and varB variables already replaced with their actual values) and if it is false it runs:
#/dev/null
which does nothing, silently.
You can set verify on around that code to see when and where substitution is happening.
You can't implement procedural logic into sqlplus. You have these options :
Implement the IF-THEN-ELSE logic inside the shell script that is running the sqlplus.
Use PL/SQL, but then your SQL Script should be called as a process inside an anonymous block, not like an external script.
In your case the easiest way is to change your shell script.
#/bin/bash
#
# load environment Oracle variables
sqlplus system/$password#$instance #./oracle/mysqlfile.sql $var1 $var2 $var3
# if then
if [ $var3 == "true" ]
then
sqlplus system/$password#$instance #./oracle/myOthersqlfile.sql
fi
You should realise that sqlplus is just a CLI ( Command Line Interface ). So you can't apply procedural logic to it.
I have no idea what you do in those sql scripts ( running DMLs, creating files, etc ), but the best approach would be to convert them to PL/SQL, then you can apply whatever logic you need to.
I am unfamiliar with linux/linux environment so do pardon me if I make any mistakes, do comment to clarify.
I have created a simple perl script. This script creates a sql file and as shown, it would execute the lines in the file to be inserted into the database.
#!/usr/bin/perl
use strict;
use warnings;
use POSIX 'strftime';
my $SQL_COMMAND;
my $HOST = "i";
my $USERNAME = "need";
my $PASSWORD = "help";
my $NOW_TIMESTAMP = strftime '%Y-%m-%d_%H-%M-%S', localtime;
open my $out_fh, '>>', "$NOW_TIMESTAMP.sql" or die 'Unable to create sql file';
printf {$out_fh} "INSERT INTO BOL_LOCK.test(name) VALUES ('wow');";
sub insert()
{
my $SQL_COMMAND = "mysql -u $USERNAME -p'$PASSWORD' ";
while( my $sql_file = glob '*.sql' )
{
my $status = system ( "$SQL_COMMAND < $sql_file" );
if ( $status == 0 )
{
print "pass";
}
else
{
print "fail";
}
}
}
insert();
This works if I execute it while I am logged in as a user(I do not have access to Admin). However, when I set a cronjob to run this file let's say at 10.08am by using the line(in crontab -e):
08 10 * * * perl /opt/lampp/htdocs/otpms/Data_Tsunami/scripts/test.pl > /dev/null 2>&1
I know the script is being executed as the sql file is created. However no new rows are inserted into the database after 10.08am. I've searched for solutions and some have suggested using the DBI module but it's not available on the server.
EDIT: Didn't manage to solve it in the end. A root/admin account was used to to execute the script so that "solved" the problem.
First things first, get rid of the > /dev/null 2>&1 at the end of your crontab entry (at least temporarily) so you can actually see any errors that may be occurring.
In other words, change it temporarily to something like:
08 10 * * * perl /opt/lampp/htdocs/otpms/Data_Tsunami/scripts/test.pl >/tmp/myfile 2>&1
Then you can examine the /tmp/myfile file to see what's being output.
The most likely case is that mysql is not actually on the path in your cron job, because cron itself gives a rather minimal environment.
To fix that problem (assuming that's what it is), see this answer, which gives some guidelines on how best to expand the cron environment to give you what you need. That will probably just involve adding the MySQL executable directory to your PATH variable.
The other thing you may want to consider is closing the out_fh file before trying to pass it to mysql - if the buffers haven't been flushed, it may still be an empty file as far as other processes are concerned.
The expression glob(".* *") matches all files in the current working
directory.
- http://perldoc.perl.org/functions/glob.html
you should not rely on the wd in a cron job. If you want to use a glob (or any file operation) with a relative path, set the wd with chdir first.
source: http://www.perlmonks.org/bare/?node_id=395387
So if your working directory is, for example /home/user, you should insert
chdir('/home/user/');
before the WHILE, ie:
sub insert()
{
my $SQL_COMMAND = "mysql -u $USERNAME -p'$PASSWORD' ";
chdir('/home/user/');
while( my $sql_file = glob '*.sql' )
{
...
replace /home/user with wherever your sql files are being created.
It's better to do as much processing within Perl as possible. It avoids the overhead of generating a separate shell process and leaves everything under the control of the program so that you can handle any errors much more simply
Database access from Perl is done using the DBI module. This program demonstrates how to achieve what you have written using the mysql utility. As you can see it's also much more concise
#!/usr/bin/perl
use strict;
use warnings;
use DBI;
my $host = "i";
my $username = "need";
my $password = "help";
my $dbh = DBI->connect("DBI:mysql:database=test;host=$host", $username, $password);
my $insert = $dbh->prepare('INSERT INTO BOL_LOCK.test(name) VALUES (?)');
my $rv = $insert->execute('wow');
print $rv ? "pass\n" : "fail\n";
I am trying to connect with database and perform some SQL queries by using this code, but every time it hangs.
my $connect_str = `/osp/local/etc/.oralgn $srv_name PSMF`;
my $sqlFile = "/osp/local/home/linus/amit/mytest.sql";
my ($abc, $cde)= split (/\#/ , $connect_str );
print "$abc";
$ORACLE_SID=SDDG00;
`export $ORACLE_SID`;
#chomp($abc);
#$abc=~ s/\s+$//;
`sqlplus $abc`;
open (SQL, "$sqlFile");
while (my $sqlStatement = <SQL>) {
$sth = dbi->prepare($sqlStatement)
or die (qq(Can't prepare $sqlStatement));
$sth->execute()
or die qq(Can't execute $sqlStatement);
}
How do I invoke a SQL command inside Perl?
Reading the documentation for the DBI module would be a good start.
Your problem seems to be this line.
$sth = dbi->prepare($sqlStatement)
You're trying to call the prepare method on the class "dbi". But you don't have a class called "dbi" in your program (or, at least, I can't see one in the code you've shown us).
To use a database from Perl you need to do these things:
1/ Load the DBI module (note, "DBI", not "dbi" - Perl is case sensitive).
use DBI;
2/ Connect to the database and get a database handle (Read the DBD::Oracle documentation for more details on the arguments to the connect() method).
my $dbh = DBI->connect('dbi:Oracle:dbname', $user, $password);
3/ You can then use this database handle to prepare SQL statements.
my $sth = $dbh->prepare($sqlStatement);
We have a Perl script which runs a SQL and puts data in the table.
Now instead of supplying a single SQL statement, we want to pass bunch of them putting them together in a .sql file. We know that our program will fail because it expects a single SQL statement, not s bunch of them (that too from a .sql file). How do we make it work with a .sql file (having multiple INSERT statements?). We are using the DBI package.
A small snippet of code:
$sth = $dbh->prepare("/home/user1/tools/mytest.sql");
$sth->execute || warn "Couldn't execute statement";
$sth->finish();
There is a sort of workaround for DDL. You need to slurp SQL file first and then enclose it's contents into BEGIN ... END; keywords. Like:
sub exec_sql_file {
my ($dbh, $file) = #_;
my $sql = do {
open my $fh, '<', $file or die "Can't open $file: $!";
local $/;
<$fh>
};
$dbh->do("BEGIN $sql END;");
}
This subroutine allows to run DDL (SQL) scripts with multiple statements inside (e.g. database dumps).
Not exactly sure what you want...
Once you create a DBI object, you can use it over and over again. Here I'm reading SQL statement after SQL statement from a file and processing each and every one in order:
use DBI;
my $sqlFile = "/home/user1/tools/mytest.sql"
my $dbh = DBI::Connect->new($connect, $user, $password)
or die("Can't access db");
# Open the file that contains the various SQL statements
# Assuming one SQL statement per line
open (SQL, "$sqlFile")
or die("Can't open file $sqlFile for reading");
# Loop though the SQL file and execute each and every one.
while (my $sqlStatement = <SQL>) {
$sth = dbi->prepare($sqlStatement)
or die("Can't prepare $sqlStatement");
$sth->execute()
or die("Can't execute $sqlStatement");
}
Notice that I'm putting the SQL statement in the prepare and not the file name that contains the SQL statement. Could that be your problem?
You don't need perl for this at all. Just use the mysql command line client:
mysql -h [hostname] -u[username] -p[password] [database name] < /home/user1/tools/mytest.sql
replace the [variables] with your information.
Note no space after -u or -p. If your mysql server is running on the same machine you can omit -h[hostname] (it defaults to localhost)
Here is how I've done it. In my case I dont assume one SQL per line and I assume, my example is a bit better :)
sub get_sql_from_file {
open my $fh, '<', shift or die "Can't open SQL File for reading: $!";
local $/;
return <$fh>;
};
my $SQL = get_sql_from_file("SQL/file_which_holds_sql_statements.sql");
my $sth1 = $dbh1->prepare($SQL);
$sth1->execute();