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How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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Hide separator line on one UITableViewCell
I'm customizing a UITableView . I want to hide the line separating on the last cell ... can i do this?
37 Answers
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How do I include negative decimal numbers in this regular expression?
How do I match negative numbers as well by this regular expression? This regex works fine with positive values, but I want it to also allow negative values e.g. -10, -125.5 etc.
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Can dplyr package be used for conditional mutating?
Can the mutate be used when the mutation is conditional (depending on the values of certain column values)?
5 Answers
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How can I remove a flag in C?
There is a variable that holds some flags and I want to remove one of them. But I don't know how to remove it.
3 Answers
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How to extract numbers from a string and get an array of ints?
I have a String variable (basically an English sentence with an unspecified number of numbers) and I'd like to extract all the numbers into an array of integers. I was wondering whether there was a quick solution with regular expressions?
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How can I declare and define multiple variables in one line using C++?
I always though that if I declare these three variables that they will all have the value 0
10 Answers
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How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
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How to read a .xlsx file using the pandas Library in iPython?
I want to read a .xlsx file using the Pandas Library of python and port the data to a postgreSQL table.
6 Answers
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How do we control web page caching, across all browsers?
Our investigations have shown us that not all browsers respect the HTTP cache directives in a uniform manner.
29 Answers
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