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Which is more efficient: Multiple MySQL tables or one large table?
...ous user details in my MySQL database. Originally it was set up in various tables meaning data is linked with UserIds and outputting via sometimes complicated calls to display and manipulate the data as required. Setting up a new system, it almost makes sense to combine all of these tables into one ...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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中文网（自研/维护）拓展 · App Inventor 2 中文网
...otherwise.
DatabasePath()
Returns the path to the database.
Delete(table,whereClause,bindParams)
Executes a SQL DELETE statement.
DeleteAsync(tag,table,whereClause,bindParams)
Executes a SQL DELETE statement, asynchronously.
DeleteDatabase()
Delete the database.
Execute(sql,bi...
How to add a WiX custom action that happens only on uninstall (via MSI)?
...ly on uninstalls - not upgrades, not repairs or modifies. According to the table above I had to use
<Custom Action='CA_ID' Before='other_CA_ID'>
(NOT UPGRADINGPRODUCTCODE) AND (REMOVE="ALL")</Custom>
And it worked!
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How to do INSERT into a table records extracted from another table
I'm trying to write a query that extracts and transforms data from a table and then insert those data into another table. Yes, this is a data warehousing query and I'm doing it in MS Access. So basically I want some query like this:
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SQL left join vs multiple tables on FROM line?
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The old syntax, with just listing the tables, and using the WHERE clause to specify the join criteria, is being deprecated in most modern databases.
It's not just for show, the old syntax has the possibility of being ambiguous when you use both INNER and OUTER j...
Difference between View and table in sql
What is the main difference between view and table in SQL. Is there any advantage of using views instead of tables.
7 Answe...
Get button click inside UITableViewCell
I have a view controller with a table view and a separate nib for the table cell template. The cell template has some buttons. I want to access the button click along with the index of the cell clicked inside the view controller where I have defined the Table view.
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COUNT DISTINCT with CONDITIONS
...tinct items in a column subject to a certain condition, for example if the table is like this:
5 Answers
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What's the difference between identifying and non-identifying relationships?
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An identifying relationship is when the existence of a row in a child table depends on a row in a parent table. This may be confusing because it's common practice these days to create a pseudokey for a child table, but not make the foreign key to the parent part of the child's primary key. Fo...