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mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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How to get values from IGrouping
I have a question about IGrouping and the Select() method.
4 Answers
4
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Procedure expects parameter which was not supplied
... data tab [beside layout and Preview tabs] next to the name of the dataset selected, there is another drop down control that lets you change the CommandType. Enjoy!
– SarjanWebDev
Aug 14 '12 at 6:17
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Differences between INDEX, PRIMARY, UNIQUE, FULLTEXT in MySQL?
...e - which are typically implemented internally using b-trees (allowing for selecting, sorting or ranges starting from left most column) or hash tables (allowing for selection starting from left most column).
Where the other index types are general-purpose, a FULLTEXT index is specialised, in that it...
Entity Framework: There is already an open DataReader associated with this Command
...al commands executed on single connection (or single command with multiple selects) while next DataReader is executed before first one has completed the reading. The only way to avoid the exception is to allow multiple nested DataReaders = turn on MultipleActiveResultSets. Another scenario when this...
Where is the 'tests output pane'?
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This is the correct answer. Selecting "Tests" from the combobox is the key.
– Keith
Aug 29 '14 at 14:51
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How to generate a new Guid in stored procedure?
... using SQL Server. I'm sure other database system have similar functions.
select NEWID()
If you're using Oracle then you can use the SYS_GUID() function. Check out the answer to this question: Generate a GUID in Oracle
sh...
SQL Server Regular expressions in T-SQL
... the database you stored the assembly in.
Then use in queries like so:
SELECT *
FROM
(
SELECT
DailyLog.Date,
DailyLog.Researcher,
DailyLog.team,
DailyLog.field,
DailyLog.EntityID,
DailyLog.[From],
DailyLog.[To],
dbo.RegexConta...
Reference - What does this error mean in PHP?
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mysql_fetch_array() expects parameter 1 to be resource, boolean given in select
All "mysql_fetch_array() expects parameter 1 to be resource, boolean given" Questions on Stackoverflow
Related Errors:
Warning: [function] expects parameter 1 to be resource, boolean given
Other mysql* functions ...
Picking a random element from a set
... the buckets that make up the hashset, which allows us to more efficiently select a random elements. If random elements are necessary in Java, it might be worthwhile to define a custom hash set that allows the user to look under the hood. See [boost's docs][1] for a little more in this. [1] boos...