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Apply multiple functions to multiple groupby columns
...unctions applied to a grouped-by dataframe: pandas.pydata.org/pandas-docs/stable/…
– IanS
May 20 '16 at 8:44
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Is there any difference between the `:key => “value”` and `key: “value”` hash notations?
...strings. Although hash-rockets provide freedom and functionality for hash-tables, specifically allowing strings as keys, application performance may be slower than if the hash-tables were to be constructed with symbols as hash-keys. The following resources may be able to clarify any differences be...
✔ Checkmark selected row in UITableViewCell
I am an iOS development newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
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How do I set the time zone of MySQL?
...ed timezones like 'Europe/Helsinki' means that you have to have a timezone table properly populated.)
Keep in mind that +02:00 is an offset. Europe/Berlin is a timezone (that has two offsets) and CEST is a clock time that corresponds to a specific offset.
@@session.time_zone variable
SELECT @@ses...
ORA-00979 not a group by expression
...ave a database like this:
FOO BAR
0 A
0 B
and you run SELECT * FROM table GROUP BY foo. This means the database must return a single row as result with the first column 0 to fulfill the GROUP BY but there are now two values of bar to chose from. Which result would you expect - A or B? Or shou...
How to use GROUP BY to concatenate strings in SQL Server?
...5 and later. Original question didn't specify the version in use.]
CREATE TABLE #YourTable ([ID] INT, [Name] CHAR(1), [Value] INT)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'A',4)
INSERT INTO #YourTable ([ID],[Name],[Value]) VALUES (1,'B',8)
INSERT INTO #YourTable ([ID],[Name],[Value]...
TSQL - How to use GO inside of a BEGIN .. END block?
...t using SET NOEXEC.
IF not whatever
BEGIN
SET NOEXEC ON;
END
ALTER TABLE dbo.EMPLOYEE ADD COLUMN EMP_IS_ADMIN BIT NOT NULL
GO
UPDATE dbo.EMPLOYEE SET EMP_IS_ADMIN = whatever
SET NOEXEC OFF;
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For loop example in MySQL
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drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedur...
How do I show the schema of a table in a MySQL database?
From the MySQL console, what command displays the schema of any given table?
5 Answers
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Spring JPA selecting specific columns
...ase operations. However I don't know how to select specific columns from a table in Spring JPA?
14 Answers
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