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“Insert if not exists” statement in SQLite
... and text you should be able to do like this:
INSERT INTO memos(id,text)
SELECT 5, 'text to insert'
WHERE NOT EXISTS(SELECT 1 FROM memos WHERE id = 5 AND text = 'text to insert');
If a record already contains a row where text is equal to 'text to insert' and id is equal to 5, then the insert op...
How to modify a global variable within a function in bash?
...alise that if you just run the function without assigning it to a variable all the global variables within it will update. Instead of returning a string array, why not just update the string array in the function then assign it to another variable after the function has finished ?
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what does the __file__ variable mean/do?
I usually just hard-wire these with the actual path. But there is a reason for these statements that determine path at runtime, and I would really like to understand the os.path module so that I can start using it.
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Exclude .svn directories from grep [duplicate]
...tput of first grep as input (via piping). By using the -v flag, grep will select the lines which DON'T match the search terms. Voila. You are left with all the ouputs from the first grep which do not contain .svn in the filepath.
-v, --invert-match
Invert the sense of matching, to select n...
Can I set a breakpoint on 'memory access' in GDB?
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Assuming the first answer is referring to the C-like syntax (char *)(0x135700 +0xec1a04f) then the answer to do rwatch *0x135700+0xec1a04f is incorrect. The correct syntax is rwatch *(0x135700+0xec1a04f).
The lack of ()s there caused me a great deal of pain trying to use watchpoints m...
How to remove an element from a list by index
...org/projects/python/trunk/Objects/listobject.c how PyList_GetItem() essentially returns ((PyListObject *)op) -> ob_item[i]; - the ith element of an array.
– glglgl
Sep 9 '13 at 7:53
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What do I use for a max-heap implementation in Python?
... amazed that there IS such a built-in solution in heapq. But then it is totally unreasonable that it is NOT even slightly mentioned at all in the official document! WTF!
– RayLuo
Apr 21 '15 at 6:48
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Improving bulk insert performance in Entity framework [duplicate]
... {
var e = entity;
table.Rows.Add(properties.Select(property => GetPropertyValue(property.GetValue(e, null))).ToArray());
}
// send it to the server for bulk execution
bulkCopy.BulkCopyTimeout = 5 * 60;
bulkCopy.WriteToServer(table);
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How to get a value of an element by name instead of ID
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Use the name attribute selector:
$("input[name=nameGoesHere]").val();
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Why is using 'eval' a bad practice?
...d eval have nothing to do with each other. An application that's fundamentally mis-designed is fundamentally mis-designed. eval is no more the root cause of bad design than division by zero or attempting to import a module which is known not to exist. eval isn't insecure. Applications are insecu...