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How to get primary key column in Oracle?
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SELECT cols.table_name, cols.column_name, cols.position, cons.status, cons.owner
FROM all_constraints cons, all_cons_columns cols
WHERE cols.table_name = 'TABLE_NAME'
AND cons.constraint_type = 'P'
AND cons.constraint_name = ...
Delete column from SQLite table
... TRANSACTION;
CREATE TEMPORARY TABLE t1_backup(a,b);
INSERT INTO t1_backup SELECT a,b FROM t1;
DROP TABLE t1;
CREATE TABLE t1(a,b);
INSERT INTO t1 SELECT a,b FROM t1_backup;
DROP TABLE t1_backup;
COMMIT;
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How to use UIScrollView in Storyboard
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Here are the steps with Auto Layout that worked for me on XCode 8.2.1.
Select Size Inspector of View Controller, and change Simulated Size to Freeform with height 1000 instead of Fixed.
Rename the view of View Controller as RootView.
Drag a Scroll View as subview of RootView and rename it as Scr...
How to increase font size in the Xcode editor?
...)
Go to XCode > Preferences > Fonts & Color
From the 'Theme' box select the theme you want to modify (or select the theme you want to modify and click the "+" button at the bottom of the theme list to clone it first for backup, for there is no undo option)
In the source editor box there is...
Check if a temporary table exists and delete if it exists before creating a temporary table
...me in SQL Server 2005, with the extra "foo" column appearing in the second select result:
IF OBJECT_ID('tempdb..#Results') IS NOT NULL DROP TABLE #Results
GO
CREATE TABLE #Results ( Company CHAR(3), StepId TINYINT, FieldId TINYINT )
GO
select company, stepid, fieldid from #Results
GO
ALTER TABLE #R...
Ordering by specific field value first
...QL FIELD function.
If you want complete sorting for all possible values:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "core", "board", "other")
If you only care that "core" is first and the other values don't matter:
SELECT id, name, priority
FROM mytable
ORDER BY FIELD(name, "co...
Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
MySQL Orderby a number, Nulls last
...Place a minus sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://t...
How to generate Class Diagram (UML) on Android Studio (IntelliJ Idea)
...ight click on the folder containing the classes you want to visualize, and select Add to simpleUML Diagram.
That's it; you have you fancy class diagram generated from your code!
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How to create an object for a Django model with a many to many field?
...dd(bar1)
foo.bars.add(bar2)
It generates a whopping total of 7 queries:
SELECT "app_bar"."id", "app_bar"."name" FROM "app_bar" WHERE "app_bar"."id" = 1
SELECT "app_bar"."id", "app_bar"."name" FROM "app_bar" WHERE "app_bar"."id" = 2
INSERT INTO "app_foo" ("name") VALUES ()
SELECT "app_foo_bars"."b...