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Select multiple records based on list of Id's with linq
...NQ to SQL implementations of query operators except the Contains operator. error when using LINQ2SQL datacontext.
– Mayank Raichura
Jan 30 '16 at 0:20
4
...
Facebook database design?
...ild it so that it will perform well but it clearly requires some trial and error and benchmarking.
Here is my disappointing test for just findings friends of friends:
DB Schema:
CREATE TABLE IF NOT EXISTS `friends` (
`id` int(11) NOT NULL,
`user_id` int(11) NOT NULL,
`friend_id` int(11) NOT N...
Which Boost features overlap with C++11?
...see the list below
gamma function (tgamma), log gamma function (lgamma)
error functions (erf, erfc)
log1p, expm1
cbrt, hypot
acosh, asinh, atanh
TR1 (they are marked in the documentation if those are TR1 libraries)
Array → std::array
Bind → std::bind
Enable If → std::enable_if
Function...
Grouped LIMIT in PostgreSQL: show the first N rows for each group?
...mn and I get "could not identify equality operator for type json postgres" error when I select distinct t_outer.section_id, t_top.*
– suat
May 10 at 11:35
...
Getters \ setters for dummies
... this.bar = value; } }; foo.bar = 456; Raises an exception: Uncaught RangeError: Maximum call stack size exceeded at Object.set bar [as bar] (<anonymous>:4:32) at Object.set bar [as bar] (<anonymous>:4:32) at Object.set bar [as bar] (<anonymous>:4:32) at Object.set...
Why doesn't Python have a sign function?
...m "value"; -0.0 is a negative number, even if that seems an implementation error. Simply using cmp() will give the desired results, probably for nearly every case anyone would care about: [cmp(zero, 0) for zero in (0, 0.0, -0.0, -4, 5)] ==> [0, 0, 0, -1, 1].
– pythonlarry
...
Can two different strings generate the same MD5 hash code?
...5f427593d849676da0d1d55d8360fb5f07fea2 | fold -w2)
--- /dev/fd/63 2016-02-05 12:55:04.000000000 +0000
+++ /dev/fd/62 2016-02-05 12:55:04.000000000 +0000
@@ -33,7 +33,7 @@
af
bf
a2
-00
+02
a8
28
4b
@@ -53,7 +53,7 @@
6d
a0
d1
-55
+d5
5d
83
60
Above collision example is taken from Marc ...
How to suppress scientific notation when printing float values?
...AltoAziz Alto
12.6k33 gold badges5656 silver badges5050 bronze badges
...
Using an ORM or plain SQL? [closed]
... I was saying: even the most basic scenarios can potentially be subject to errors in different DBMSes - for instance, different handling of NULLs.
– Anton Gogolev
Jan 30 '09 at 8:17
...
Postgres and Indexes on Foreign Keys and Primary Keys
...- or a bad index
WITH fk_actions ( code, action ) AS (
VALUES ( 'a', 'error' ),
( 'r', 'restrict' ),
( 'c', 'cascade' ),
( 'n', 'set null' ),
( 'd', 'set default' )
),
fk_list AS (
SELECT pg_constraint.oid as fkoid, conrelid, confrelid as parentid,
co...