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Are soft deletes a good idea? [duplicate]
...ow have to include a WHERE IsDeleted = false clause in every query on this table (and so much worse if you're JOINing these tables). A mistake here would be caught as soon as a user or tester noticed a deleted record showing up again, which might take some time. Also, it would be easy for a develo...
An efficient compression algorithm for short text strings [closed]
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Check out Smaz:
Smaz is a simple compression library suitable for compressing very short
strings.
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SQL exclude a column using SELECT * [except columnA] FROM tableA?
We all know that to select all columns from a table, we can use
41 Answers
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How to append rows to an R data frame
...O I come with 4 distinct solutions:
rbindlist to the data.frame
Use data.table's fast set operation and couple it with manually doubling the table when needed.
Use RSQLite and append to the table held in memory.
data.frame's own ability to grow and use custom environment (which has reference seman...
SQL Server NOLOCK and joins
...argument, just your original question.
Yes, you need WITH(NOLOCK) on each table of the join. No, your queries are not the same.
Try this exercise. Begin a transaction and insert a row into table1 and table2. Don't commit or rollback the transaction yet. At this point your first query will retu...
postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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How to get the mysql table columns data type?
I want to get the column data type of a mysql table.
11 Answers
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How to Use slideDown (or show) function on a table row?
I'm trying to add a row to a table and have that row slide into view, however the slidedown function seems to be adding a display:block style to the table row which messes up the layout.
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Code Golf: Collatz Conjecture
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@Martinho: Me too, but thanks to lazy evaluation, the tables are even much cooler than in other languages.
– Dario
Mar 6 '10 at 19:46
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Altering column size in SQL Server
How to change the column size of the salary column in the employee table from numeric(18,0) to numeric(22,5)
6 Answe...