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How to create user for a db in postgresql? [closed]
I have installed PostgreSQL 8.4 on my CentOS server and connected to root user from shell and accessing the PostgreSQL shell.
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Oracle 分组后取每组第一条数据 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...组后取每组第一条数据Oracle 分组后取每组第一条数据的SQL如下，亲测有效：SELECT * FROM (SELECT ROW_NUMBER() OVER(PARTITION BY T field1, T Oracle 分组后取每组第一条数据的SQL如下，亲测有效：
SELECT *
FROM (SELECT ROW_NUMBER() OVER(PARTITION ...
Linq 多字段排序，二次排序 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ordered = source.OrderByDescending( t => t.f1 ).ThenBy( t => t.f2 );类似SQL：select * from t1 order by f1 d...Linq：ordered = source.OrderByDescending( t => t.f1 ).ThenBy( t => t.f2 );
类似SQL：select * from t1 order by f1 desc ,f2 asc
这种写法里 OrderBy、ThenBy 是升序的，Ord...
- App Inventor 2 离线版 - 清泛IT社区，为创新赋能！
数据存储 抽屉中的 微数据库 组件。键值存储，用法很简单，看下文档就行了。
如果需要 sql 数据库，使用 SQLite 拓展：拓展，拓展市场，搜索 sql
mongoose vs mongodb (nodejs modules/extensions), which better? and why?
...you're looking for an object modeling (ODM, a counterpart to ORMs from the SQL world) tool to skip some lower level work, you want Mongoose.
If you want a driver, because you intend to break a lot of rules that an ODM might enforce, go with MongoDB. If you want a fast driver, and can live with some...
SHA1 vs md5 vs SHA256: which to use for a PHP login?
... you've made it. Again this could be a disgruntled employee XSS attack or sql injection or some other attack that has nothing to do with your password encryption.
I do believe you should still encrypt but the only thing I can see the encryption does is prevent people that already have or somehow ...
Fastest way to count exact number of rows in a very large table?
...r independent solution = use the standard = COUNT(*)
There are approximate SQL Server solutions but don't use COUNT(*) = out of scope
Notes:
COUNT(1) = COUNT(*) = COUNT(PrimaryKey) just in case
Edit:
SQL Server example (1.4 billion rows, 12 columns)
SELECT COUNT(*) FROM MyBigtable WITH (NOLOCK...
Do you use source control for your database items? [closed]
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With Mysql Workbench you can have all that in a structured file(xml) that can be opened and handled with a GUI. Being xml just text, yes it can be versioning without having to type single sql sentence.
– levhi...
How to edit multi-gigabyte text files? Vim doesn't work =( [closed]
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Great tip. I had a 13GB (152.000.000 lines) sql-file, and just using "split -l 1000000" then editing the one million line files where I wanted with vim worked great. Took 10 minutes just to split them. (I tried to open the original file with vim and that worked, but it...
NOT using repository pattern, use the ORM as is (EF)
...stead of constrained to a consistent location creates the EF equivalent of SQL calls in codebehind pages. Every LINQ query is a potential maintenance point in an application, and the more there are (and the more widespread they are), the higher the maintenance costs and risks. Imagine adding a 'de...