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MySQL/SQL: Group by date only on a Datetime column
Having a table with a column like: mydate DATETIME ...
4 Answers
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Find all storage devices attached to a Linux machine [closed]
I have a need to find all of the writable storage devices attached to a given machine, whether or not they are mounted.
7...
How to Create Multiple Where Clause Query Using Laravel Eloquent?
... You can also pass an array of conditions like this: $users = DB::table('users')->where([ ['status', '=', '1'], ['subscribed', '<>', '1'], ])->get();
– zeros-and-ones
Sep 15 '16 at 19:19
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Count(*) vs Count(1) - SQL Server
...uld be evaluated as per ANSI
b) Otherwise, let TX be the single-column table that is the
result of applying the <value expression> to each row of T
and eliminating null values. If one or more null values are
eliminated, then a completion cond...
How can I prevent SQL injection in PHP?
...ng "'Sarah'; DELETE FROM employees", and you will not end up with an empty table.
Another benefit of using prepared statements is that if you execute the same statement many times in the same session it will only be parsed and compiled once, giving you some speed gains.
Oh, and since you asked abo...
Practical uses of different data structures [closed]
...ound the list in a similar question, previously on StackOverflow:
Hash Table - used for fast data lookup - symbol table for compilers,
database indexing, caches,Unique data representation.
Trie - dictionary, such as one found on a mobile telephone for
autocompletion and spell-checking.
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Is having an 'OR' in an INNER JOIN condition a bad idea?
... to improve the speed of an immensely slow query (several minutes on two tables with only ~50,000 rows each, on SQL Server 2008 if it matters), I narrowed down the problem to an OR in my inner join, as in:
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Is there a way to access the “previous row” value in a SELECT statement?
I need to calculate the difference of a column between two lines of a table. Is there any way I can do this directly in SQL? I'm using Microsoft SQL Server 2008.
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Count work days between two dates
...their post, I just added holidays to the function (This assumes you have a table "tblHolidays" with a datetime field "HolDate".
--Changing current database to the Master database allows function to be shared by everyone.
USE MASTER
GO
--If the function already exists, drop it.
IF EXISTS
(
SEL...
How do I convert from BLOB to TEXT in MySQL?
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Usage: SELECT CONVERT(column USING utf8) FROM table;
– bmaupin
Oct 2 '12 at 19:32
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