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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 ...
Equivalent of varchar(max) in MySQL?
...are a varchar of the maximum row size, even if it's the only column in the table.
mysql> CREATE TABLE foo ( v VARCHAR(65534) );
ERROR 1118 (42000): Row size too large. The maximum row size for the used table type, not counting BLOBs, is 65535. This includes storage overhead, check the manual. Yo...
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 ...
What is the most efficient/elegant way to parse a flat table into a tree?
Assume you have a flat table that stores an ordered tree hierarchy:
14 Answers
14
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How can I change the table names when using ASP.NET Identity?
... "Individual User Accounts" for authentication. This creates the following tables:
7 Answers
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Unique constraint on multiple columns
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By using the constraint definition on table creation, you can specify one or multiple constraints that span multiple columns. The syntax, simplified from technet's documentation, is in the form of:
CONSTRAINT constraint_name UNIQUE [ CLUSTERED | NONCLUSTERED ]
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How to make Sequelize use singular table names
I have an model called User but Sequelize looks for the table USERS whenever I am trying to save in the DB. Does anyone know how to set Sequelize to use singular table names? Thanks.
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Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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Declare variable in table valued function
How can I declare a variable in a table valued function? (like in my title)
1 Answer
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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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