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EF Code First “Invalid column name 'Discriminator'” but no inheritance
...othing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF Proxy Class.
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Use tnsnames.ora in Oracle SQL Developer
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everyone, Just a little update on this old (but quite helpfull) post : don't try to use a symbolic link on Windows. SQL developper doesn't seem to know how to use it. Made me lose some time. Hope it'll save yours.
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GROUP BY with MAX(DATE) [duplicate]
...ated columns in your result set which are not grouped. If a train has only one destination, then just add the destination column to your group by clause, otherwise you need to rethink your query.
Try:
SELECT t.Train, t.Dest, r.MaxTime
FROM (
SELECT Train, MAX(Time) as MaxTime
FROM Trai...
How do I pause my shell script for a second before continuing?
...5m # Waits 5 minutes.
sleep 5h # Waits 5 hours.
sleep 5d # Waits 5 days.
One can also employ decimals when specifying a time unit; e.g. sleep 1.5s
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Altering a column: null to not null
...bove two correct responses. The semantics of NULL can have a few meanings. One of the common meaning is UNKNOWN. Take SCORE as an example. A null SCORE and a ZERO SCORE is a world of difference! Before you did the above recommendations. Make sure you application does not take null in its business lo...
What is a “static” function in C?
...e variable". This is Smalltalk terminology. This means that there is only one copy of a static data member shared by all objects of a class, while each object has its own copy of a non-static data member. So a static data member is essentially a global variable, that is a member of a class.
Non-s...
Check if list contains element that contains a string and get that element
While searching for an answer to this question, I've run into similar ones utilizing LINQ but I haven't been able to fully understand them (and thus, implement them), as I'm not familiarized with it. What I would like to, basically, is this:
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Regular expression to match DNS hostname or IP Address?
Does anyone have a regular expression handy that will match any legal DNS hostname or IP address?
21 Answers
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MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
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Collapse sequences of white space into a single character and trim string
...icate predicateWithFormat:@"SELF != ''"];
NSArray *parts = [theString componentsSeparatedByCharactersInSet:whitespaces];
NSArray *filteredArray = [parts filteredArrayUsingPredicate:noEmptyStrings];
theString = [filteredArray componentsJoinedByString:@" "];
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