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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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How to select rows that have current day's timestamp?
I am trying to select only today's records from a database table.
9 Answers
9
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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Select something that has more/less than x character
Was wondering if it's possible to select something that has more/less than x characters in SQL.
4 Answers
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jQuery UI: Datepicker set year range dropdown to 100 years
...wn: either relative to today's year ("-nn:+nn"), relative to the currently selected year ("c-nn:c+nn"), absolute ("nnnn:nnnn"), or combinations of these formats ("nnnn:-nn"). Note that this option only affects what appears in the drop-down, to restrict which dates may be selected use the minDate and...
MySQL combine two columns into one column
...does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two ways to add a space:
select concat(column1, ' ', column2)
select concat_ws(' ', column1, column2)
share
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PreparedStatement IN clause alternatives?
... and cons of each is available here.
The suggested options are:
Prepare SELECT my_column FROM my_table WHERE search_column = ?, execute it for each value and UNION the results client-side. Requires only one prepared statement. Slow and painful.
Prepare SELECT my_column FROM my_table WHERE search_...
How to map and remove nil values in Ruby
...blem:
N = 1_00_000
enum = 1.upto(1_000)
Benchmark.bmbm do |x|
x.report("select + map") { N.times { enum.select { |i| i.even? }.map{|i| i + 1} } }
x.report("map + compact") { N.times { enum.map { |i| i + 1 if i.even? }.compact } }
x.report("filter_map") { N.times { enum.filter_map { |i| i ...
MFC Grid control 2.27 - C/C++ - 清泛网 - 专注IT技能提升
...ading this thing if no one is gonna use it.
The control features:
Cell selection using the mouse, with optional Control and Shift key combinations. Selection can be disabled.
Row and Column resizing. Sizing can be disabled for row, columns or both.
Auto row or column sizing when dividers are d...
MFC Grid control 2.27 - C/C++ - 清泛网 - 专注IT技能提升
...ading this thing if no one is gonna use it.
The control features:
Cell selection using the mouse, with optional Control and Shift key combinations. Selection can be disabled.
Row and Column resizing. Sizing can be disabled for row, columns or both.
Auto row or column sizing when dividers are d...