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Best way to check if object exists in Entity Framework?
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hi. how can we check if it exists and after that select all its data?
– virtouso
Apr 7 '15 at 1:27
1
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Datetime equal or greater than today in MySQL
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SELECT * FROM users WHERE created >= CURDATE();
But I think you mean created < today
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Checking if a SQL Server login already exists
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From here
If not Exists (select loginname from master.dbo.syslogins
where name = @loginName and dbname = 'PUBS')
Begin
Select @SqlStatement = 'CREATE LOGIN ' + QUOTENAME(@loginName) + '
FROM WINDOWS WITH DEFAULT_DATABASE=[PUBS], DEFAULT...
How to enable MySQL Query Log?
...global general_log = 1;
SET global log_output = 'table';
View the log
select * from mysql.general_log;
Disable Query logging on the database
SET global general_log = 0;
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Google Play Services Library update and missing symbol @integer/google_play_services_version
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control click -> properties -> android -> libraries, add -> select the project you just imported -> ok
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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...
How to add ASP.NET 4.0 as Application Pool on IIS 7, Windows 7
...t to Windows 7.
One of the things that I need to run the application is to select ASP.NET v4.0 as the application pool within IIS.
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Cannot drop database because it is currently in use
...ar(50)
SET @DatabaseName = N'YOUR_DABASE_NAME'
DECLARE @SQL varchar(max)
SELECT @SQL = COALESCE(@SQL,'') + 'Kill ' + Convert(varchar, SPId) + ';'
FROM MASTER..SysProcesses
WHERE DBId = DB_ID(@DatabaseName) AND SPId <> @@SPId
--SELECT @SQL
EXEC(@SQL)
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How to save CSS changes of Styles panel of Chrome Developer Tools?
...oper Tools, Right-click in the left panel (where the files are listed) and select Add Folder to Workspace. You can get to a stylesheet in the Sources panel quickly by clicking the stylesheet at the top-right of each CSS rule for a selected element in the Elements panel.
After adding the folder,...