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When NOT to use Cassandra?
...by one in the same order you asked them. Since Cassandra is based on the NoSQL family of databases, it's important you understand why use a NoSQL database before I answer your questions.
Why use NoSQL
In the case of RDBMS, making a choice is quite easy because all the databases like MySQL, Oracle,...
How to select only the first rows for each unique value of a column
...h multiple columns, athough not with bit-type columns. I tested this in MS SQL server 2016 though.
– netfed
Sep 8 '18 at 23:59
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VC菜单命令详解(文件打开、保存与关闭) - C/C++ - 清泛网 - 专注C/C++及内核技术
...构造the main frame对象和the main frame window，但不显示它，它包括IDR_MAINFRAME、the toolbar、the status bar；
3、构造view对象和view窗口，但不显示它；
4、建立the document、main frame、view对象之间的关系，这里要借助AddDocTemplate建立的类关系...
How do I rename a column in a SQLite database table?
I would need to rename a few columns in some tables in a SQLite database.
I know that a similar question has been asked on stackoverflow previously, but it was for SQL in general, and the case of SQLite was not mentioned.
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Select statement to find duplicates on certain fields
Can you help me with SQL statements to find duplicates on multiple fields?
7 Answers
7...
SQL query to find record with ID not in another table
...d has a limited number of values cf : dba-oracle.com/t_maximum_number_of_sql_in_list_values.htm
– G.Busato
Feb 19 '18 at 11:04
2
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Liquibase lock - reasons?
...EQUENCE_NAME_SEQ"/>
</changeSet>
A work around is using plain SQL to check this instead:
<changeSet author="user" id="123">
<preConditions onFail="CONTINUE">
<sqlCheck expectedResult="0">
select count(*) from user_sequences where sequen...
IDENTITY_INSERT is set to OFF - How to turn it ON?
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Reminder
SQL Server only allows one table to have IDENTITY_INSERT property set to ON.
This does not work:
SET IDENTITY_INSERT TableA ON
SET IDENTITY_INSERT TableB ON
... INSERT ON TableA ...
... INSERT ON TableB ...
SET IDENTITY_INS...
Rails where condition using NOT NIL
... should use references here as well, otherwise you may end up with invalid SQL.
Foo.includes(:bar)
.references(:bar)
.merge(Bar.where.not(id: nil))
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Code-first vs Model/Database-first [closed]
...t
IMHO popular if you are designer fan (= you don't like writing code or SQL).
You will "draw" your model and let workflow generate your database script and T4 template generate your POCO entities. You will lose part of the control on both your entities and database but for small easy projects you...