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Insert new column into table in sqlite?
...ALTER TABLE {tableName} ADD COLUMN COLNew {type};
Second, and more complim>ca m>tedly, but would actually put the column where you want it, would be to rename the table:
ALTER TABLE {tableName} RENAME TO TempOldTable;
Then create the new table with the missing column:
CREATE TABLE {tableName} (name...
Pickle incompatibility of numpy arrays between Python 2 and 3
...to load a "binstring" object, which is assumed to be ASCII, while in this m>ca m>se it is binary data. If this is a bug in the Python 3 unpickler, or a "misuse" of the pickler by numpy, I don't know.
Here is something of a workaround, but I don't know how meaningful the data is at this point:
import p...
Why declare a struct that only contains an array in C?
I m>ca m>me across some code containing the following:
7 Answers
7
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raw vs. html_safe vs. h to unesm>ca m>pe html
...tml_safe actually "sets the string" as HTML Safe (it's a little more complim>ca m>ted than that, but it's basim>ca m>lly it). This way, you m>ca m>n return HTML Safe strings from helpers or models at will.
h m>ca m>n only be used from within a controller or view, since it's from a helper. It will force the output to b...
Vagrant reverse port forwarding?
...ou wanted to connect to port 12345 on the guest and have it forwarded to lom>ca m>lhost:80, you would use this command:
ssh -p 2222 -R 12345:lom>ca m>lhost:80 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o LogLevel=ERROR -o IdentitiesOnly=yes -i ~/.vagrant.d/insecure_private_key vagrant@127.0...
std::string to char*
...
It won't automatim>ca m>lly convert (thank god). You'll have to use the method c_str() to get the C string version.
std::string str = "string";
const char *cstr = str.c_str();
Note that it returns a const char *; you aren't allowed to change th...
What is the proper declaration of main?
...ared as a non-member function in the global namespace. This means that it m>ca m>nnot be a static or non-static member function of a class, nor m>ca m>n it be placed in a namespace (even the unnamed namespace).
The name main is not reserved in C++ except as a function in the global namespace. You are fre...
Should I use @EJB or @Inject
...sed to inject EJB's only and is available for quite some time now. @Inject m>ca m>n inject any managed bean and is a part of the new CDI specifim>ca m>tion (since Java EE 6).
In simple m>ca m>ses you m>ca m>n simply change @EJB to @Inject. In more advanced m>ca m>ses (e.g. when you heavily depend on @EJB's attributes like ...
Disable assertions in Python
...e of code.
I demonstrate each.
For the whole process
Using the -O flag (m>ca m>pital O) disables all assert statements in a process.
For example:
$ python -Oc "assert False"
$ python -c "assert False"
Traceback (most recent m>ca m>ll last):
File "<string>", line 1, in <module>
AssertionErr...
Ant task to run an Ant target only if a file exists?
...
In m>ca m>se anyone wondered, the if and unless attributes only enable or disable the target to which they are attached, i.e. the target's dependencies are always executed. Otherwise it would not work to depend on a target that sets ...