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Can I combine :nth-child() or :nth-of-type() with an arbitrary selector?
...ot match) an arbitrary selector ? For example, I want to select every odd table row, but within a subset of the rows:
7 An...
Select multiple columns in data.table by their numeric indices
...ltiple columns using a vector of their numeric indices (position) in data.table ?
5 Answers
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Fast way to discover the row count of a table in PostgreSQL
I need to know the number of rows in a table to calculate a percentage. If the total count is greater than some predefined constant, I will use the constant value. Otherwise, I will use the actual number of rows.
...
MFC AfxMessageBox改变标题的几种方法 - C/C++ - 清泛网 - 专注C/C++及内核技术
...工程名的基础上改变标题呢？其实这个标题在资源String Table里就能找到，查找AFX_IDS_APP_TITLE，在这里你就能轻而易举的改变标题了。
注意：如果工程的资源String Table里面没有添加AFX_IDS_APP_TITLE，需要手动添加。
2、修改m_pszA...
__FILE__, __LINE__, and __FUNCTION__ usage in C++
...on using the strings utility to extract all string-like data from the executable. Even compressed executables can be extracted. Be very mindful of what you send out to a customer site. Often times competitors are able to get their hands on your executables, even though they are not supposed to do...
Inner join vs Where
...
No! The same execution plan, look at these two tables:
CREATE TABLE table1 (
id INT,
name VARCHAR(20)
);
CREATE TABLE table2 (
id INT,
name VARCHAR(20)
);
The execution plan for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FRO...
What is the difference between a stored procedure and a view?
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A view represents a virtual table. You can join multiple tables in a view and use the view to present the data as if the data were coming from a single table.
A stored procedure uses parameters to do a function... whether it is updating and inserting ...
What are the uses for Cross Join?
...t
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might cross three tables:
select
hour,
minute
from
hours CROSS JOIN minute...
MySQL table is marked as crashed and last (automatic?) repair failed
I was repairing this table suddenly server hanged and when I returned back all tables are ok but this one showing 'in use' and when I try to repair it doesn't proceed.
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Entity Framework: table without primary key
...That's fine, I suppose, but keep in mind that the OP asked about mapping a table without a primary key, not a view. The answer is still the same. Working around the EF's need to have a PK on tables is a bad idea from the standpoint of manageability, data integrity, and performance.
Some have comm...