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How to find the size of an array in postgresql
...ikely) and are running PostgreSQL 9.4 or higher, you can use cardinality:
SELECT cardinality(id) FROM example;
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Executing multi-line statements in the one-line command-line?
...rt sys
for r in range(3): print 'rob'
EOF
in latter case leading tab characters are removed too (and some structured outlook can be achieved)
instead of EOF can stand any marker word not appearing in the here document at a beginning of a line (see also here documents in the bash manpage or he...
Learning assembly [closed]
...y contents (in assembly language, hexadecimal or ASCII), make changes, and selectively execute COM, EXE and other file types.
It also has several subcommands which are used to access specific disk
sectors, I/O ports and memory addresses. MS-DOS Debug runs at a
16-bit process level and therefor...
Disabling user selection in UIWebView
...use I want the user to be able to click links. I just need to disable user selection. I found somewhere in the Internets that you can use:
...
How can we match a^n b^n with Java regex?
...finalized pattern, with additional test cases, including one that's 10,000 characters long:
$tests = array(
'aaa', 'aaab', 'aaaxb', 'xaaab', 'b', 'abbb', 'aabb', 'aaabbbbb', 'aaaaabbb',
'', 'ab', 'abb', 'aab', 'aaaabb', 'aaabbb', 'bbbaaa', 'ababab', 'abc',
str_repeat('a', 5000).str_repeat('b',...
Change auto increment starting number?
...foobar(moobar) values ("def");
INSERT INTO foobar(moobar) values ("xyz");
select * from foobar;
'10', 'abc'
'11', 'def'
'12', 'xyz'
This auto increments the id column by one starting at 10.
Auto increment in MySQL by 5, starting at 10:
drop table foobar
create table foobar(
id IN...
What is the use of GO in SQL Server Management Studio & Transact SQL?
...
gbn make it SELECT and look at what happens :-)
– SQLMenace
Feb 19 '10 at 21:09
14
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GROUP BY with MAX(DATE) [duplicate]
... to your group by clause, otherwise you need to rethink your query.
Try:
SELECT t.Train, t.Dest, r.MaxTime
FROM (
SELECT Train, MAX(Time) as MaxTime
FROM TrainTable
GROUP BY Train
) r
INNER JOIN TrainTable t
ON t.Train = r.Train AND t.Time = r.MaxTime
...
How can I suppress column header output for a single SQL statement?
...in batch (using the mysql command-line binary). I want one of my several SELECT statements to not print the column headers, just the selected records. Is this possible?
...
How can I easily convert DataReader to List? [duplicate]
... writing an extension method for this:
public static IEnumerable<T> Select<T>(this IDataReader reader,
Func<IDataReader, T> projection)
{
while (reader.Read())
{
yield return projection(reader);
}
}
You can then use LINQ...