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Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
...es. Also, not all situations are quite handled- for example, if you try to select from table foo while another transaction is dropping it and creating a replacement table foo, then the blocked transaction will finally receive an error rather than finding the new foo table. (Edit: this was fixed in o...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
... I'm using caches on multiple levels anyway. You can always explicitly use SELECT SQL_CACHE <rest of statement> though.
– Will Morgan
May 4 '12 at 16:37
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Stop Visual Studio from launching a new browser window when starting debug?
...ed answer for a .NET Core Web Api project...
Right-click on your project, select "Properties," go to "Debug" and untick the "Launch browser" checkbox (enabled by default).
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How do I rename a column in a database table using SQL?
...any other RDBMS), you can do it with regular ALTER TABLE statement:
=> SELECT * FROM Test1;
id | foo | bar
----+-----+-----
2 | 1 | 2
=> ALTER TABLE Test1 RENAME COLUMN foo TO baz;
ALTER TABLE
=> SELECT * FROM Test1;
id | baz | bar
----+-----+-----
2 | 1 | 2
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Best way to check for nullable bool in a condition expression (if …)
...en you are trying to evaluate a nullable bool in linq.
For example:
array.Select(v => v.nullableBool ?? false)
(from v in array where v.nullableBool ?? false)
Is cleaner in my opinion as opposed to:
array.Select(v => v.nullableBool.HasValue ? v.nullableBool.Value : false)
(from v in array wh...
One or more types required to compile a dynamic expression cannot be found. Are you missing referenc
...
On your solution explorer window, right click to References, select Add Reference, go to .NET tab, find and add Microsoft.CSharp.
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How can I write a regex which matches non greedy? [duplicate]
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The non-greedy ? works perfectly fine. It's just that you need to select dot matches all option in the regex engines (regexpal, the engine you used, also has this option) you are testing with. This is because, regex engines generally don't match line breaks when you use .. You need to tell ...
Storing time-series data, relational or non?
...evation.
Correction
It is not "filtering out the un-needed data"; it is selecting only the needed data. Yes, of course, if you have an Index to support the columns identified in the WHERE clause, it is very fast, and the query does not depend on the size of the table (grabbing 1,000 rows from a ...
Android Studio Gradle Configuration with name 'default' not found
...:
Go to your sub-project-module/library-module settings. (press F4 after selecting the module)
Right Click on Add > Android-Gradle.
Add build.gradle to your module.
Add the following script
buildscript {
repositories {
mavenCentral()
}
dependencies {
classpath 'com.android.tools.bu...
Deleting all records in a database table
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Prefer select whenever you need to use an if expression inside a block, this way you avoid having to chain the compact method to remove nil elements.
– Sebastian Palma
Jan 18 '18 at 17:18
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