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What is the MySQL VARCHAR max size?
...QL has a maximum row size limit
The internal representation of a MySQL table has a maximum row size limit of 65,535 bytes, not counting BLOB and TEXT types. BLOB and TEXT columns only contribute 9 to 12 bytes toward the row size limit because their contents are stored separately from the rest of...
Database: To delete or not to delete records
...t possible of course) an aggregation scheme, and shove that off to another table. This will keep your primary table clean of 'deleted' data, as well as keep your secondary table optimized for monitoring purposes (or whatever you had in mind).
For temporal data, see: http://talentedmonkeys.wordpress...
Django: How to completely uninstall a Django app?
...dy management command that will give you the necessary SQL to drop all the tables for an app. See the sqlclear docs for more information. Basically, running ./manage.py sqlclear my_app_name gets you get the SQL statements that should be executed to get rid of all traces of the app in your DB. You st...
Vertical (rotated) text in HTML table
Is there a (portable) way to rotate text in a HTML table cell by 90°?
11 Answers
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How to select multiple rows filled with constants?
Selecting constants without referring to a table is perfectly legal in an SQL statement:
15 Answers
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Split function equivalent in T-SQL?
...to split '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15...' (comma delimited) into a table or table variable.
15 Answers
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Non-Relational Database Design [closed]
...a stores that don't use traditional relational design or SQL (such as Hypertable, CouchDB, SimpleDB, Google App Engine datastore, Voldemort, Cassandra, SQL Data Services, etc.). They're also often referred to as "key/value stores", and at base they act like giant distributed persistent hash tables.
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The model backing the context has changed since the database was created
...eded to use the model with a hash of the schema stored in an
EdmMetadata table that is created with a database (when Code First is
the one creating the database). Existing databases won’t have the
EdmMetadata table and so won’t have the hash…and the implementation
today will throw if t...
What does android:layout_weight mean?
...specify a size ratio between multiple views. E.g. you have a MapView and a table which should show some additional information to the map. The map should use 3/4 of the screen and table should use 1/4 of the screen. Then you will set the layout_weight of the map to 3 and the layout_weight of the tab...
Should I index a bit field in SQL Server?
...k for a set of rows, SQL uses the index to find the rows more quickly than table scanning (looking at every row).
SQL has clustered and non-clustered indexes. My understanding of clustered indexes is that they group similar index values into the same page. This way when you ask for all the rows m...