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Difference between Fact table and Dimension table?
When reading a book for business objects, I came across the term- fact table and dimension table.
9 Answers
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How to delete a row by reference in data.table?
My question is related to assignment by reference versus copying in data.table . I want to know if one can delete rows by reference, similar to
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How to change a table name using an SQL query?
How can I in change the table name using a query statement?
10 Answers
10
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Simple Pivot Table to Count Unique Values
This seems like a simple Pivot Table to learn with. I would like to do a count of unique values for a particular value I'm grouping on.
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How can you represent inheritance in a database?
...e SQL Entity-Attribute-Value antipattern. This is a brief overview:
Single Table Inheritance (aka Table Per Hierarchy Inheritance):
Using a single table as in your first option is probably the simplest design. As you mentioned, many attributes that are subtype-specific will have to be given a NULL v...
Eliminate extra separators below UITableView
When I set up a table view with 4 rows, there are still extra separators lines (or extra blank cells) below the filled rows.
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How do I UPDATE from a SELECT in SQL Server?
In SQL Server , it is possible to insert rows into a table with an INSERT.. SELECT statement:
35 Answers
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How to drop column with constraint?
... problematic DEFAULT constraint, after that you can drop the column
alter table tbloffers drop constraint [ConstraintName]
go
alter table tbloffers drop column checkin
But the error may appear from other reasons - for example the user defined function or view with SCHEMABINDING option set for th...
How to force table cell content to wrap?
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Use table-layout:fixed in the table and word-wrap:break-word in the td.
See this example:
<html>
<head>
<style>
table {border-collapse:collapse; table-layout:fixed; width:310px;}
table td {border:soli...
Fast way to discover the row count of a table in PostgreSQL
I need to know the number of rows in a table to calculate a percentage. If the total count is greater than some predefined constant, I will use the constant value. Otherwise, I will use the actual number of rows.
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