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PDOException SQLSTATE[HY000] [2002] No such file or directory
...basic) site to fortrabbit, but as soon as I connect to SSH to run some commands (such as php artisan migrate or php artisan db:seed ) I get an error message:
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ORA-12514 TNS:listener does not currently know of service requested in connect descriptor
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I had this issue and the fix was to make sure in tnsnames.ora the SERVICE_NAME is a valid service name in your database. To find out valid service names, you can use the following query in oracle:
select value from v$parameter where name='se...
Practical usage of setjmp and longjmp in C
Can anyone explain me where exactly setjmp() and longjmp() functions can be used practically in embedded programming? I know that these are for error handling. But I'd like to know some use cases.
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Best way to select random rows PostgreSQL
I want a random selection of rows in PostgreSQL, I tried this:
12 Answers
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How to delete duplicate rows in SQL Server?
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I like CTEs and ROW_NUMBER as the two combined allow us to see which rows are deleted (or updated), therefore just change the DELETE FROM CTE... to SELECT * FROM CTE:
WITH CTE AS(
SELECT [col1], [col2], [col3], [col4], [col5], [col6]...
Standardize data columns in R
I have a dataset called spam which contains 58 columns and approximately 3500 rows of data related to spam messages.
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What is Castle Windsor, and why should I care?
I'm a long-time Windows developer, having cut my teeth on win32 and early COM. I've been working with .NET since 2001, so I'm pretty fluent in C# and the CLR. I'd never heard of Castle Windsor until I started participating in Stack Overflow. I've read the Castle Windsor "Getting Started" guide, b...
What does %~dp0 mean, and how does it work?
I find %~dp0 very useful, and I use it a lot to make my batch files more portable.
7 Answers
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How to tell if a string is not defined in a Bash shell script
...Autoconf, you'll find that they do not recommend combining terms with '-a' and do recommend using separate simple tests combined with &&. I've not encountered a system where there is a problem; that doesn't mean they didn't used to exist (but they are probably extremely rare these days, eve...
Truncate Two decimal places without rounding
Lets say I have a value of 3.4679 and want 3.46, how can I truncate to two decimal places that without rounding up?
21 Answ...