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How do you concatenate Lists in C#?
... old but I came upon this post quickly thinking Concat would be my answer. Union worked great for me. Note, it returns only unique values but knowing that I was getting unique values anyway this solution worked for me.
namespace TestProject
{
public partial class Form1 :Form
{
publ...
What database does Google use?
... with different time stamps. The time stamp allows for operations such as "select 'n' versions of this Web page" or "delete cells that are older than a specific date/time."
In order to manage the huge tables, Bigtable splits tables at row boundaries and saves them as tablets. A tablet is around 20...
#1071 - Specified key was too long; max key length is 767 bytes
...
767 bytes is the stated prefix limitation for InnoDB tables in MySQL version 5.6 (and prior versions). It's 1,000 bytes long for MyISAM tables. In MySQL version 5.7 and upwards this limit has been increased to 3072 bytes.
You also have to be aware that if you set an index on a big char ...
Can we pass parameters to a view in SQL?
..., like:
CREATE FUNCTION v_emp (@pintEno INT)
RETURNS TABLE
AS
RETURN
SELECT * FROM emp WHERE emp_id=@pintEno;
This allows you to use it as a normal view, with:
SELECT * FROM v_emp(10)
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MySQL 启动报错 Table \'mysql.plugin\' doesn\'t exist - 数据库(内核) -...
MySQL 启动报错 Table 'mysql.plugin' doesn't exist 启动报错： opt szy bin mysqld: Table 'mysql.plugin ' doesn 't exist141211 15:06:12 [ERROR] Can 't open t...启动报错：
/opt/szy/bin/mysqld: Table \'mysql.plugin\' doesn\'t exist
141211 15:06:12 [ERROR] Can\'t open the mysql.plug...
MySQL - Make an existing Field Unique
...
ALTER IGNORE TABLE mytbl ADD UNIQUE (columnName);
For MySQL 5.7.4 or later:
ALTER TABLE mytbl ADD UNIQUE (columnName);
As of MySQL 5.7.4, the IGNORE clause for ALTER TABLE is removed and
its use produces an error.
So, make sure to remove duplicate entries first as IGNO...
Detect application heap size in Android
... an Android version such as CyanogenMod, which allows the user to manually select how large a heap size should be allowed for each app. In CM, for example, this option appears under "CyanogenMod settings" / "Performance" / "VM heap size".
NOTE: BE AWARE THAT SETTING THIS VALUE MANUALLY CAN MESS U...
App Inventor 2 DynamicComponents 拓展：动态创建AI2组件对象 · App Inventor 2 中文网
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通过 JSON 字符串创建组件。请参阅Wiki，了解如何创建自己的模板。
从屏幕和组件列表中移除指定 ID 的组件。由于该组件已被删除，因此你可以再次使用该 ID...
How many levels of pointers can we have?
...eclarators (in any combinations) modifying an
arithmetic, structure, union, or void type in a declaration
The upper limit is implementation specific.
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How to Join to first row
...
SELECT Orders.OrderNumber, LineItems.Quantity, LineItems.Description
FROM Orders
JOIN LineItems
ON LineItems.LineItemGUID =
(
SELECT TOP 1 LineItemGUID
FROM LineItems
W...