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Retrieving the last record in each group - MySQL
There is a table messages that contains data as shown below:
27 Answers
27
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What is the difference between a stored procedure and a view?
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A view represents a virtual table. You can join multiple tables in a view and use the view to present the data as if the data were coming from a single table.
A stored procedure uses parameters to do a function... whether it is updating and inserting ...
How to read the database table name of a Model instance?
Given a model's instance object, how can I get the database table's name?
1 Answer
1
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Want to find records with no associated records in Rails
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Just imagine you have 10000000 records in friends table. What about performance in that case?
– goodniceweb
Dec 20 '16 at 14:51
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Physical vs. logical / soft delete of database record?
...and you don't have to worry about cascading a delete through various other tables in the database that reference the row you are deleting. Disadvantage is that you have to code any reporting/display methods to take the flag into account.
As far as if it is a common practice - I would say yes, but ...
How do you create a yes/no boolean field in SQL server?
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And if you link the table in an Access database, true will have the value -1 and false will have the value 0. At least in Access 2003. (This is the version I had handy that was connected to a customer's MSSQL database).
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App Inventor Tutorials and Examples: Dynamic Table Layout | Pura Vida Apps
...vacy Policy Contact Dynamic Table Layout and Table Listpicker Thank you Christopher for being the sponsor of the App Inventor 2 version! It was asked in the App Inventor Forum, how to display a table in App Inventor without knowing how m...
How to append rows to an R data frame
...O I come with 4 distinct solutions:
rbindlist to the data.frame
Use data.table's fast set operation and couple it with manually doubling the table when needed.
Use RSQLite and append to the table held in memory.
data.frame's own ability to grow and use custom environment (which has reference seman...
Set NOW() as Default Value for datetime datatype?
I have two columns in table users namely registerDate and lastVisitDate which consist of datetime data type. I would like to do the following.
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How to check if a column exists in a SQL Server table?
...HERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL
BEGIN
-- Column Exists
END
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