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UITableView : viewForHeaderInSection: not called during reloadData:
I've set up the tableview with correct delegate and datasource linkages.. the reloadData method calls the datasource and the delegate methods except for viewForHeaderInSection: .
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SQL query for finding records where count > 1
I have a table named PAYMENT . Within this table I have a user ID, an account number, a ZIP code and a date. I would like to find all records for all users that have more than one payment per day with the same account number.
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What's the best practice for primary keys in tables?
When designing tables, I've developed a habit of having one column that is unique and that I make the primary key. This is achieved in three ways depending on requirements:
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Postgres DB Size Command
... of all the databases that you can connect to from the "pg_datbase" system table. Just apply the function to the names, as below.
select t1.datname AS db_name,
pg_size_pretty(pg_database_size(t1.datname)) as db_size
from pg_database t1
order by pg_database_size(t1.datname) desc;
If you int...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ions:
Individual insert/update operations in a retry loop; or
Locking the table and doing batch merge
Individual row retry loop
Using individual row upserts in a retry loop is the reasonable option if you want many connections concurrently trying to perform inserts.
The PostgreSQL documentation co...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
I have created my tables in my SQLiteOpenHelper onCreate() but receive
15 Answers
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XAMPP - MySQL shutdown unexpectedly
...course, destroy all the data which was stored in that file (all the InnoDB tables which were created before setting innodb_file_per_table to enabled). The methods suggested in the log message seem suprtior to me.
– Tgr
Oct 12 '13 at 10:50
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How to disable scrolling in UITableView table when the content fits on the screen
I have a few (grouped style) tables in my iphone app (only on part of the screen and added with Interface Builder though, not subclassed from UITableViewController ) that 80% of the time are small and will fit on the screen. When the table fits on the screen, I'd like to disable scrolling, to ma...
Relational Database Design Patterns? [closed]
...elationships using a foreign key.
Many-to-Many relationships with a bridge table.
Optional one-to-one relationships managed with NULLs in the FK column.
Star-Schema: Dimension and Fact, OLAP design.
Fully normalized OLTP design.
Multiple indexed search columns in a dimension.
"Lookup table" that con...
Auto increment primary key in SQL Server Management Studio 2012
How do I auto increment the primary key in a SQL Server database table, I've had a look through the forum but can't see how.
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