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How to write a JSON file in C#?
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@RobertHarvey Liam's Json.Net link has a nice table showing what the differences are. Coming from the people that make it, of course you should take it with a grain of salt, but it is indeed better than the built-in things.
– Tim S.
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how can I Update top 100 records in sql server
I want to update the top 100 records in SQL Server. I have a table T1 with fields F1 and F2 . T1 has 200 records. I want to update the F1 field in the top 100 records. How can I update based on TOP 100 in SQL Server?
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B-Tree vs Hash Table
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You can only access elements by their primary key in a hashtable.
This is faster than with a tree algorithm (O(1) instead of log(n)), but you cannot select ranges (everything in between x and y).
Tree algorithms support this in Log(n) whereas hash indexes can result in a full table s...
What's the purpose of SQL keyword “AS”?
You can set table aliases in SQL typing the identifier right after the table name.
9 Answers
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SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
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Cascade will work when you delete something on table Courses. Any record on table BookCourses that has reference to table Courses will be deleted automatically.
But when you try to delete on table BookCourses only the table itself is affected and not on the Courses
foll...
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...
What's the best manner of implementing a social activity stream? [closed]
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I have created such system and I took this approach:
Database table with the following columns: id, userId, type, data, time.
userId is the user who generated the activity
type is the type of the activity (i.e. Wrote blog post, added photo, commented on user's photo)
data is a seriali...
select into in mysql
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Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
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Center a DIV horizontally and vertically [duplicate]
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Nice to have a version without table-cell, thanks.
– devlord
Dec 20 '13 at 19:01
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App Inventor 2 SQLite 拓展：超流行兼容主流SQL语法的迷你本地数据库引擎...
...数据表
创建一个测试数据表，sql如下：
CREATE TABLE users (
id INTEGER PRIMARY KEY,
name TEXT,
age INTEGER);
数据表信息
这时，可以查看一下表信息：
插入数据
往 users 表中插入...