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Querying data by joining two tables in two database on different servers
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Once the link is established, you can also use OPENQUERY to execute a SQL statement on the remote server and transfer only the data back to you. This can be a bit faster, and it will let the remote server optimize your query. If you cache the data in a temporary (or in-memory) table on DB1 in...
When and why are database joins expensive?
...x strategy is available to the optimiser.
I used to be smarter than the MSSQL optimiser. That changed two versions ago. Now it generally teaches me. It is, in a very real sense, an expert system, codifying all the wisdom of many very clever people in a domain sufficiently closed that a rule-based s...
StringUtils 字符串工具扩展：强大的文本处理工具集 · App Inventor 2 中文网
...的文本处理工具函数。它提供了丰富的字符串操作方法，包括字符检测、文本提取、填充、验证等功能。
主要功能
字符和大小写检测
文本提取（左、右、中间）
文本填充和居中
字符串缩写
ASCII 码...
Get the Query Executed in Laravel 3/4
How can I retrieve the raw executed SQL query in Laravel 3/4 using Laravel Query Builder or Eloquent ORM?
20 Answers
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How can I temporarily disable a foreign key constraint in MySQL?
Is it possible to temporarily disable constraints in MySQL?
10 Answers
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Why use a READ UNCOMMITTED isolation level?
... Oracle has "snapshot" by default since I know it, probably decades before Sql Server introduced it. I was quite disappointed when starting with SQL Server and I found out that all concurrency problems were solved using "primitive" locking mechanisms. Never saw "Read uncommitted" in Oracle. And the ...
How to remove a column from an existing table?
...n do this by querying system tables or using third party tools such as ApexSQL Search (free) or Red Gate Dependency tracker (premium but more features). There a whole thread on foreign keys here
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Laravel Eloquent: How to get only certain columns from joined tables
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I tried this and it shows an error SQLSTATE[42S22]: Column not found and it's SQL doesn't include the table in the with. The sql that it appears on the error is "SELECT fk_table.column1 FROM main_table".
– Michel Ayres
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How do I get SUM function in MySQL to return '0' if no values are found?
Say I have a simple function in MySQL:
4 Answers
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LINQ To Entities does not recognize the method Last. Really?
...n comes down to the fact that eventually it has to translate that query to SQL and SQL has a SELECT TOP (in T-SQL) but not a SELECT BOTTOM (no such thing).
There is an easy way around it though, just order descending and then do a First(), which is what you did.
EDIT:
Other providers will possibly...