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LINQ-to-SQL vs stored procedures? [closed]
...umber of supported databases will only increase. Sprocs are not always portable between databases, either because of varying syntax or feature support (if the database supports sprocs at all).
Deployment: Others have mentioned this already, but it's easier to deploy a single assembly than to deploy...
How to include “zero” / “0” results in COUNT aggregate?
...u want an outer join for this (and you need to use person as the "driving" table)
SELECT person.person_id, COUNT(appointment.person_id) AS "number_of_appointments"
FROM person
LEFT JOIN appointment ON person.person_id = appointment.person_id
GROUP BY person.person_id;
The reason why this is wo...
How to understand nil vs. empty vs. blank in Ruby
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I made this useful table with all the cases:
blank?, present? are provided by Rails.
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How to use Servlets and Ajax?
...gt; as JSON
Here's an example which displays List<Product> in a <table> where the Product class has the properties Long id, String name and BigDecimal price. The servlet:
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, I...
SQLite: How do I save the result of a query as a CSV file?
...ex = False)
You can customize the query to only export part of the sqlite table to the CSV file.
You can also run a single command to export all sqlite tables to CSV files:
for table in c.execute("SELECT name FROM sqlite_master WHERE type='table';").fetchall():
t = table[0]
df = pd.read_sql...
Changing column names of a data frame
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Try setnames() in the data.table package. Use something like setnames(DT,"b","B") or setnames(DT,c("a","E"),c("A","F"))
– dwstu
Aug 11 '14 at 17:23
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Django migration strategy for renaming a model and relationship fields
...different name, and the migration it creates will lose any data in the old table." Django 2.1 Docs For me, it was sufficient to create an empty migration, add the model renames to it, then run makemigrations as usual.
– hlongmore
Jan 15 '19 at 9:05
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Difference between Divide and Conquer Algo and Dynamic Programming
...blem is solved only once and the result of each sub-problem is stored in a table ( generally implemented as an array or a hash table) for future references. These sub-solutions may be used to obtain the original solution and the technique of storing the sub-problem solutions is known as memoization....
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...at is generated is sub-optimal.
For example, if you send SELECT *
FROM table WHERE id BETWEEN 1 AND
99999999, the DBMS may select a
full-table scan instead of an index
scan because you're grabbing every row
in the table (so sayeth the
statistics). If this is the cached
version, then ...
Should I commit or rollback a read transaction?
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Suppose I create a temp table, populate it with ids, join it with a data table to select the data that goes with the ids, then delete the temp table. I'm really just reading data, and I don't care what happens to the temp table, since it's temporar...