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How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
PostgreSQL: Difference between text and varchar (character varying)
... article does detailed testing to show that the performance of inserts and selects for all 4 data types are similar. It also takes a detailed look at alternate ways on constraining the length when needed. Function based constraints or domains provide the advantage of instant increase of the length c...
SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
...
How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
How do I create a SQL table under a different schema?
...er 2008
1. Navigate to Security > Schemas
2. Right click on Schemas and select New Schema
3. Complete the details in the General tab for the new schema. Like, the schema name is "MySchema" and the schema owner is "Admin".
4. Add users to the schema as required and set their permissions:
5. Add an...
Can you use an alias in the WHERE clause in mysql?
...ts an unknown column. Is there any way to get around this issue? I need to select records that have a rating higher than x. Rating is calculated as the following alias:
...
SQL Server 2008 can't login with newly created user
...ick on SQL Server instance at root of Object Explorer, click on Properties
Select Security from the left pane.
Select the SQL Server and Windows Authentication mode radio button, and click OK.
Right-click on the SQL Server instance, select Restart (alternatively, open up Services and restart the ...
Android Studio doesn't see device
..., follow these steps:
1. go to Run
2. Click on Edit Configurations
3. Select the project
4. find the Target Device section under the General tab on the Android Application page.
That seems to be where you toggle what the project builds to. If you're importing a project it actually defaults t...
What does jquery $ actually return?
...
From Rick Strahl's description:
The jQuery Object: The Wrapped Set:
Selectors return a jQuery object known
as the "wrapped set," which is an
array-like structure that contains all
the selected DOM elements. You can
iterate over the wrapped set like an
array or access individual elem...
Android studio add external project to build.gradle
...ick module -> Open Module Settings -> Dependencies -> + (bottom), select Module Dependency, select your library from the list, click ok :)
– T.Coutlakis
Jan 11 '15 at 22:51
...
