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What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
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postgresql: INSERT INTO … (SELECT * …)
...ostgres
CREATE TABLE tblA (id serial, time integer);
INSERT INTO tblA
SELECT id, time
FROM dblink('dbname=dbtest', 'SELECT id, time FROM tblB')
AS t(id integer, time integer)
WHERE time > 1000;
TABLE tblA;
id | time
----+------
1 | 5000
2 | 2000
(2 rows)
PostgreSQL has ...
Search All Fields In All Tables For A Specific Value (Oracle)
...based on
what I think it should be named but it
returned no results.*
SELECT * from dba_objects WHERE
object_name like '%DTN%'
A column isn't an object. If you mean that you expect the column name to be like '%DTN%', the query you want is:
SELECT owner, table_name, column_name FROM all_tab...
how to exclude null values in array_agg like in string_agg using postgres?
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SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
SELE...
What do people find difficult about C pointers? [closed]
... left till someone tries to build a compiler.
"Memory is memory is memory" Casting just changes which versions of operators or how much room the compiler gives for a particular chunk of memory. You know you're dealing with this problem when people talk about "what (primitive) variable X really is".
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C/C++ with GCC: Statically add resource files to executable/library
...t uniform, then char is probably the most convenient: take its address and cast the pointer to the proper type as you traverse the data.
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Get record counts for all tables in MySQL database
...get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
19 Answers
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Create a temporary table in a SELECT statement without a separate CREATE TABLE
Is it possible to create a temporary (session only) table from a select statement without using a create table statement and specifying each column type? I know derived tables are capable of this, but those are super-temporary (statement-only) and I want to re-use.
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selecting unique values from a column
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Use the DISTINCT operator in MySQL:
SELECT DISTINCT(Date) AS Date FROM buy ORDER BY Date DESC;
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