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How to create function that returns nothing
...o I make use of this function inside of another function? If I try without SELECT * FROM stamp_user(...), then I get error: query has no destination for result data and if I just write stamp_user(...) then I get syntax error.
– pir
Dec 22 '18 at 18:28
...
mysql check collation of a table
...ry INFORMATION_SCHEMA.TABLES and get the collation for a specific table:
SELECT TABLE_SCHEMA
, TABLE_NAME
, TABLE_COLLATION
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = 't_name';
that gives a much more readable output in contrast to SHOW TABLE STATUS that contains a lot of irreleva...
LINQ to Entities only supports casting EDM primitive or enumeration types with IEntity interface
...i eventually found the solution which was for my extension method to call .Select(e => e as T) where T is the child class and e is the base class.
full details are here:
Create IQueryable<T> extension using base class in EF
...
Difference between string object and string literal [duplicate]
...fference. s1 will refer to an interned String object. This means, that the character sequence "abcde" will be stored at a central place, and whenever the same literal "abcde" is used again, the JVM will not create a new String object but use the reference of the cached String.
s2 is guranteed to be...
In Eclipse, what can cause Package Explorer “red-x” error-icon when all Java sources compile without
...ers e.g __duplicatefile.java . To fix this, rightclick on the project and select : Show In > Navigator . Then delete the duplicate files with underscore and build your project.
– GraSim
May 29 '15 at 10:28
...
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[...
Commit changes to a different branch than the currently checked out branch with subversion
... It must not be the root of the repository, less to duplicate in that way;
Select TortoiseSVN -> "Branch/tag...";
Set To URL: "svn://host/repository/FooBar/branches/FooBarBranchName";
Make sure [*] Working copy is selected. This will ensure the changes are commited;
Log message: "Experimenting wi...
SQL Server Installation - What is the Installation Media Folder?
... Server 2019 Developer version. Was lost with dialog prompted from step 3 "Select installation media". This Andy Leonard blog helped me: 1. Downloaded installation package from SQL Server downloads. 2. Launch downloaded wizard > Select installation type > Download media 3. Right-click on the d...
MySQL foreign key constraints, cascade delete
...RITY DEFINER
BEGIN
DELETE FROM
`products`
WHERE
`id` IN (
SELECT `products_id`
FROM `categories_products`
WHERE `categories_id` = category_ID
)
;
DELETE FROM `categories`
WHERE `id` = category_ID;
END
You also need to add the following foreign key constraints...
Where to place the 'assets' folder in Android Studio?
...
Select the app folder and then:
File > New > folder > assets Folder ,
the default location is inside /main folder
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