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How to concatenate strings of a string field in a PostgreSQL 'group by' query?
...parated_names FROM things;
--> ERROR: syntax error at or near "ORDER"
Tested on PostgreSQL 8.3.
CREATE FUNCTION string_agg_transfn(text, text, text)
RETURNS text AS
$$
BEGIN
IF $1 IS NULL THEN
RETURN $2;
ELSE
RETURN $1 ||...
PostgreSQL Autoincrement
...t;=0)
);
ALTER SEQUENCE table1_seq OWNED BY table1.col_a;
If you wish to test how MySQL is different, run the following on a MySQL database:
CREATE TABLE table1 (
uid int unsigned NOT NULL AUTO_INCREMENT PRIMARY KEY,
col_b int unsigned NOT NULL
);
INSERT INTO table1 (col_b) VALUES(1);
INSERT...
Tricks to manage the available memory in an R session
...ean out anything you're no longer using, and as an added benefit will have tested your code.
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JavaScript function similar to Python range()
...
+1 Great idea! Could you implement also step argument and test it on the values from my answer? Your answer is great for the applications where we have very specific browsers in mind (it won't work in Google Chrome, Safari and IE version earlier than 9: stackoverflow.com/a/2209743/5...
How to change column order in a table using sql query in sql server 2005?
...es. A simple example below:
http://sqlfiddle.com/#!3/67af4/1
CREATE TABLE TestTable (
Column1 INT,
Column2 VARCHAR(255)
);
GO
insert into TestTable values(1, 'Test1');
insert into TestTable values(2, 'Test2');
GO
select * from TestTable;
GO
ALTER TABLE TestTable ADD Column2_NEW VARCHAR(2...
Why static classes cant implement interfaces? [duplicate]
... application I want to use a Repository that will do the raw data access ( TestRepository , SqlRepository , FlatFileRepository etc).
Because such a repository would be used throughout the runtime of my application it seemed like a sensible thing to me to make it a static class so I could go
...
Rank function in MySQL
...ows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT INTO person VALUES (2, 'Jane', 20, 'F');
INSERT INTO person VALUES (3, 'Jack', ...
What does “Could not find or load main class” mean?
..." - which means no package declaration at the top of the file. For a quick test of some code, I did: javac TestCode.java followed by java TestCode
– Someone Somewhere
Jan 3 '16 at 17:12
...
Does Git warn me if a shorthand commit ID can refer to 2 different commits?
...
'git <command> [<revision>...] -- [<file>...]'
I just tested this on a real Git repository, by finding commits with duplicate prefixes like this:
git rev-list master | cut -c-4 | sort | uniq -c | sort -nr | head
This takes the list of revisions in master, cuts out the first 4...
What's the purpose of META-INF?
...nly directory where configuration files can be referenced both by the unit tests and the controllers. If another directory worked that would be great -- it doesn't (at least not straightforwardly). To me, building a Jar file just to test a war file is like building a car so you can walk to the kit...