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Relational table naming convention [closed]
...rd Filing Systems [characterised by Record IDs which are implemented in an SQL database container for convenience):
the tables are the Subjects of the database, thus they are nouns, again, singular
the relationships between the tables are the Actions that take place between the nouns, thus they ar...
How to return result of a SELECT inside a function in PostgreSQL?
I have this function in PostgreSQL, but I don't know how to return the result of the query:
2 Answers
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How to organize a node app that uses sequelize?
...rdinarily you would use select from two or more tables, or a union in pure SQL, you would have to run separate queries, and with the async nature of Node it's just added complexity.
Therefore I moved away from using Sequelize. Moreover I am switching from using ANY data fetching from DB in the mod...
Bulk insert with SQLAlchemy ORM
Is there any way to get SQLAlchemy to do a bulk insert rather than inserting each individual object. i.e.,
10 Answers
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Does Entity Framework Code First support stored procedures?
...E" statements in your code.
For EF 4.2:
var customers = context.Database.SqlQuery<Customer>("select * from customers")
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What is the difference between UNION and UNION ALL?
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Both UNION and UNION ALL concatenate the result of two different SQLs. They differ in the way they handle duplicates.
UNION performs a DISTINCT on the result set, eliminating any duplicate rows.
UNION ALL does not remove duplicates, and it therefore faster than UNION.
Note: While us...
Mapping composite keys using EF code first
Sql server table:
4 Answers
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select、poll、epoll之间的区别总结[整理] - C/C++ - 清泛网 - 专注C/C++及内核技术
...下：
1、select实现
select的调用过程如下所示：
（1）使用copy_from_user从用户空间拷贝fd_set到内核空间
（2）注册回调函数__pollwait
（3）遍历所有fd，调用其对应的poll方法（对于socket，这个poll方法是sock_poll，sock_poll根据情况会...
Transaction marked as rollback only: How do I find the cause
...is exception while running my application.
Finally the problem was on the sql query. i mean that the query is wrong.
please verify your query. This is my suggestion
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MySQL - UPDATE query based on SELECT Query
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You can actually do this one of two ways:
MySQL update join syntax:
UPDATE tableA a
INNER JOIN tableB b ON a.name_a = b.name_b
SET validation_check = if(start_dts > end_dts, 'VALID', '')
-- where clause can go here
ANSI SQL syntax:
UPDATE tableA SET validation_c...