I have the folllowing perl code:
my $dbo_prd = DBI->connect(
"dbi:Oracle:host=$db_srv_prd;port=1521;sid=$db_sid_prd",
$db_user_prd,
$db_pass_prd
) || warn &senderror("TREE_STRUCTURE.Could not connect to $db_srv_prd: $DBI::errstr\n");
print "\n\nconnection:" . $dbo_prd . "\n";
if ($dbo_prd != 1){
print "in prod prepare\n\n";
my $query1_prd = $dbo_prd->prepare(
"INSERT INTO CMSV2.CMS_INBOX VALUES (
'vmsdk', (SELECT SYSDATE from DUAL), 'NODE_TREE_UPDATE',?,?,?,?,NULL,NULL
)"
) || warn &senderror("TREE_STRUCTURE.Could not prepare to $db_srv_prd: $DBI::errstr\n");
}
The issues that I'm having is that I thought if the connect didn't work it would set the connection $dbo_prd to undef but it is setting it to 1? This is not what the documentation states anywhere.
The connection is being printed out as "1" when it fails and a hash which it is supposed to if it succeeds.
You have a precedence error here:
|| warn
That is assigning the return value of warn to your variable when the connect fails. Use this instead:
or warn
(warn, like print, returns 1 if successful.)
Always use the low precedence and/or for flow control between what are essentially different expressions; only use the high precedence &&/|| within what is essentially all one expression (e.g. my $foo = $bar eq 'a' || $bar eq 'b').
Related
I'm practicing some basic coding, I'm running a simple math program running in the terminal on Visual Studio Code.
How do I create an option to return to the beginning of the program, or exit the program after getting caught in an if statement?
Example:
#beginning of program
user_input=input('Please select "this" or "that": ')
findings=user_input
If findings == this:
print(this)
# How can I redirect back to first user input question, instead
# of just ending here?
if findings == that:
print (that)
# Again, How do I redirect back to first user input, instead of
# the program ending here?
# Can I setup a Play_again here with options to return to user_input,
# or exit program? And then have all other If statements
# redirect here after completion? How would I do that? with
# another If? or with a for loop?
#end program
You can try wrapping the whole program in a while loop like this:
while(True):
user_input=input('Please select "this" or "that": ')
this = 'foo'
if user_input == this:
print(this)
continue
if user_input == this:
print(this)
continue
Unfortunately, that 'another technique' I thought of using didn't work.
Here's the code (the first example modified):
import sys
def main():
# Lots of setup code here.
def start_over():
return #Do nothing and continue from the next line
condition = 1==1 #Just a sample condition, replace it with "check(condition)".
float_condition = condition
def play(*just_define:bool):
if not just_define:
play_again = input('play again? "y" or "n"')
if play_again == 'y':
start_over() #Jump to the beginning of the prohram.
if play_again == 'n':
sys.exit() #Exit the program
while True:
if float_condition == True:
# print(float_condition)
play() #skip to play_again from here?
if float_condition == False:
#print(float_condition)
play() #skip to play_again from here?
#I removed the extra "main()" which was here because it'd cause an infinite loop-like error.
main()
Output:
play again? "y" or "n"y
play again? "y" or "n"n
Process finished with exit code 0
The * in the play(*just_define:bool) function makes the just_define parameter optional. Use the parameter if you want to only tell Python to search for this function, so it doesn't throw a ReferenceError and not execute anything that's after the line if not just_define:. How to call like so: play(just_define=True).
I've used nested functions. I've defined play so that you can call it from other places in your code.
Thanks to #Hack3r - I was finally able to choose to return back to the beginning of the program or exit out. But it resulted in a new issue. Now my print(results) are printing 4 or 5 times...
Here is the actual code I built and am working with:
def main():
math_Options=['Addition +','Subtraction -','Multiplication *','Division /']
math_func=['+','-','*','/']
for options in math_Options:
print(options)
print('Lets do some Math! What math function would you like to use? ')
while True:
my_Math_Function = input('Please make your choice from list above using the function symbol: ')
my_Number1=input('Please select your first number: ')
x=float(my_Number1)
print('Your 1st # is: ', x)
my_Number2=input('Please select your Second Number: ')
y=float(my_Number2)
print('Your 2nd # is: ', y)
z=float()
print('')
for Math_function in math_func:
if my_Math_Function == math_func[0]:
z=x+y
if my_Math_Function == math_func[1]:
z=x-y
if my_Math_Function == math_func[2]:
z=x*y
if my_Math_Function == math_func[3]:
z=x/y
if (z % 2) == 0 and z>0:
print(z, ' Is an EVEN POSITIVE Number')
if (z % 2) == 1 and z>0:
print(z, ' IS a ODD POSTIVE Number')
if (z % 2) == 0 and z<0:
print(z, ' Is an EVEN NEGATIVE Number')
if (z % 2) ==1 and z<0:
print(z, ' IS a ODD NEGATIVE Number')
if z==0:
print(z, 'Is is Equal to Zero')
print('')
play_again=input('Would you like to play again? "y" or "n" ')
if play_again == 'y':
continue
if play_again == 'n':
break
main()
main()
I am facing an issue with some SQL scripts where I use parameter passing.
I call a script like this:
DEFINE sowner = "SOWNER"
DEFINE auser = "AUSER"
DEFINE tbsp = "TAB"
DEFINE insp = "IND"
#R1/do_your_job.sql $owner $auser $tbsp $insp
And inside R1/do_your_job :
define sowner = $1
define auser = $2
define tbsp = $3
define insp = $4
alter session set current_schema=$sowner;
And I get: Ora 00911: invalid character marking my $ sign
Why is it not decoding $sowner to "SOWNER"?
My file is marked with "set define $" anyway...
Thank you.
Use '&variable' while passing and '&1', '&2' etc while reading.
DEFINE sowner = "SOWNER"
DEFINE auser = "AUSER"
DEFINE tbsp = "TAB"
DEFINE insp = "IND"
#R1/do_your_job.sql &sowner &auser &tbsp &insp
Your do_your_job.sql may use it as
select '&1','&2','&3','&4' from dual;
Result
#R1/do_your_job.sql &sowner &auser &tbsp &inspSQL> SQL> SQL> SQL> SQL>
old 1: select '&1','&2','&3','&4' from dual
new 1: select 'SOWNER','AUSER','TAB','IND' from dual
'SOWNE 'AUSE 'TA 'IN
------ ----- --- ---
SOWNER AUSER TAB IND
I am trying to execute an oracle sql query in while loop of a PERL script as follows --
my $dbh = DBI->connect( 'dbi:Oracle:'.$dbname,
$dbusername,
$pass,
{ PrintError => 0,
RaiseError => 1
}
) || die "Erreur lors de la connexion: $DBI::errstr";
print ("Connexion à la base de données $dbname avec $dbusername OK \n");
$requete = "select distinct to_char(date_appli,'yyyymmdd') from DATE_APPLI ".
"where frequence = 'Q' and actif = 1";
$sth_sql = $dbh->prepare($requete);
$sth_sql->execute();
#row=$sth_sql->fetchrow_array;
$datesitu=#row[0];
$sth_sql->finish;
print "La date de situation est $datesitu \n";
# SQL to get validation script and table names
$requete = "select SCRIPT_NAME, table_name from fdf_scripts";
$sth_sql = $dbh->prepare($requete);
$sth_sql->execute();
$sth_sql->bind_columns(undef, \$script_name, \$table_name);
while ($sth_sql->fetch()) {
$script_sql="$sql_path\\"."FDF_Test_scripts\\".$script_name.".sql"; #validation script path
$script_log="$log_path\\".$script_name.".log"; #log files path
$rep_file_name="$sql_path\\"."FDF_Test_scripts\\".$table_name.".sql"; #reports SQL path
$csv_file="$sql_path\\"."FDF_Test_scripts\\".$table_name.".csv"; #report CSV path
#Load data into validation tables using validation scripts
$CmdText="sqlplus -s $connect \#$script_sql $script_log";
print "Inserting data into table : $table_name \n";
#system ("$CmdText");
$col_sql = "select COLUMN_NAME from all_tab_cols where TABLE_NAME = upper(\'$table_name\')\n";
print "$col_sql\n";
$sth_sql = $dbh->prepare($col_sql);
$sth_sql->execute();
$sth_sql->bind_columns(undef, \$COLUMN_NAME);
while ($sth_sql->fetch()) {
print "$COLUMN_NAME\n";
}
if (open (my $fh, '<:encoding(UTF-8)', $script_log)){
while (my $line = <$fh>){
if ($line=~m/\bERROR\b/){
print "Error While Loading $table_name table Please Check log file for errors at: $script_log \n";
}
}
}
else {
warn "Could open file: $script_log \n"
}
}
in above code i am fetching table names from a table and then looping them to get the column names of each table which is present in that table.
The code got executed for one iteration of inner while loop but throw error for next iteration as below --
DBD::Oracle::st fetch failed: ERROR no statement executing (perhaps you need to call execute first) [for Statement "select COLUMN_N\
AME from all_tab_cols where TABLE_NAME = upper('FDF_Bond_validation_results')
I am not proficient in PERL and just started to using this and not sure how can i overcome this problem.
Please let me know if more information is required.
In the loop, the line $sth_sql = $dbh->prepare($col_sql); overwrite the content of the $sth_sql variable. The second time the loop run, the content of $sth_sql isn't the same and the statement that overwrote it has already been exhausted (trying to fetch from it again is what causes the error).
To correct this issue you should either use a different name for the second $sth_sql variable or simply declare the second $sth_sql variable with my to keep it inside the loop (see perldoc -f my).
Note: This solution has been identified by JGNI in the comment of the question. My role has only be to summarize the issue to provide a proper answer to this question.
I am trying to set variables for gnuplot environment with set for cycle command.
I am using 4.6 version and according the gnuplot documention (page 70) the syntax is following:
for [intvar = start:end{:increment}]
for [stringvar in "A B C D"]
Examples:
set for [i = 1:10] style line i lc rgb "blue"
But i get this error:
gnuplot> set for [var in gpvars] replace(var,'#_#',' ')
^
line 0: Unrecognized option. See 'help set'.
My script:
#!/bin/bash
OUTDIRNAME="out"
TIMEFORMAT='%d.%m.%y'
GPPARS=( "xlabel "Time"" "ylabel "value1"" "y2label "value2"" "format x "%H:%M"")
GPPARS_MOD=()
for (( i=0; i < ${#GPPARS[#]}; i++)); do
FILE=${GPPARS[${i}]}
echo "arg=${FILE}"
GPPARS_MOD+=( "`echo "${FILE}" | sed -e 's/ /#_#/g'`" )
done
gnuplot << EOF
reset
replace(S,C,R)=(strstrt(S,C)) ? \
replace( S[:strstrt(S,C)-1].R.S[strstrt(S,C)+strlen(C):] ,C,R) : S
set terminal png
set output "${OUTDIRNAME}/graph.png"
set timefmt "${TIMEFORMAT}"
set xdata time
gpvars="${GPPARS_MOD[#]}"
set for [var in gpvars] {
replace(var,'#_#',' ')
}
...
EOF
...
exit 0
I am also using function replace, because spaces ( gnuplot ignores escape sequences )The function works flawlessly for plot for cycle.
I have tried with and without function and with variables without spaces, but the result is same.
As a side note -- I'm not sure that I believe your bash array will group things the way you want it to ... for me, your quotations get stripped. try:
GPPARS=( "xlabel 'Time'" "ylabel 'value1'" "y2label 'value2'" "format x '%H:%M'")
instead. (interior double quotes replaced with single quotes)
This is a tricky one -- It's a good thing you're using gnuplot 4.6, otherwise I'm not sure how to go about solving it. (EDIT -- using gnuplot 4.4, you could use a combination of word, words, if, reread, exists and macros, but it's quite a messy solution)
Note that what you have doesn't work because it is akin to:
MYLABEL='xlabel "foo"'
set MYLABEL
Gnuplot doesn't expand MYLABEL prior to doing the set command so that you can do things like:
MYLABEL="totally cool X label here!"
set xlabel MYLABEL
What you want could be accomplished using macros (but alas, not with iteration):
set macro
MYLABEL='xlabel "foo"'
set #MYLABEL
But that doesn't quite work here either because macro expansion happens before anything else (e.g. function evaluation). What you need here is gnuplot's more general iteration introduced in 4.6 combined with eval
do for [ var in gpvars ] {
eval( 'set '.replace(var,'#_#',' ') )
}
EDIT -- gnuplot 4.2+ solution
#top of script -- Nothing should go here.
replace(S,C,R)=(strstrt(S,C)) ? \
replace( S[:strstrt(S,C)-1].R.S[strstrt(S,C)+strlen(C):] ,C,R) : S
if( ! exists("N") ) N=1
TODO="${GPPARS_MOD[#]}"
set macro
do_set=replace(word(TODO,N),'#_#',' ')
set #do_set
N=N+1
if( N <= words(TODO) ) reread
#rest of script here ...
I'm using the pg gem to talk to PostgreSQL from Ruby. Is there a
better way to check if there are no results than using res.ntuples == 0?
conn = PGconn.connect config
cmd = "select * from labels inner join labels_mail using(label_id) " +
"where labels_mail.mail_id = $1 and labels.name = $2"
res = conn.exec(cmd, [mail_id, mailbox])
if res.ntuples == 0 # <=== is there a better way to check this?
cmd = "insert into labels_mail (mail_id, label_id) values ($1, $2)"
conn.exec(cmd, [mail_id, label_id(mailbox)])
end
ntuples, a typo? It is faster and concise to use zero? than == 0
if res.num_tuples.zero?