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When to Redis? When to MongoDB? [closed]
... need to change your schema quickly.
Because there is no schema! Altering tables in traditional, relational DBMS is painfully expensive and slow. MongoDB solves this problem by not making a lot of assumptions on your underlying data. Nevertheless, it tries to optimize as far as possible without req...
How do you rename a table in SQLite 3.0?
How do you rename a table in SQLite 3.0?
2 Answers
2
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How can I modify the size of column in a MySQL table?
I have created a table and accidentally put varchar length as 300 instead of 65353 . How can I fix that?
2 Answers
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Save PL/pgSQL output from PostgreSQL to a CSV file
...rticular directory, for instance, and the filename might have to have a suitable prefix or extension.
Which tables should the user be able to read/write in the database? This would normally be defined by GRANTs in the database, but the function is now running as a superuser, so tables which would no...
Convert char to int in C and C++
...e subtracted from each other. Since 0 comes directly before 1 in the ascii table (and so on until 9), the difference between the two gives the number that the character a represents.
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Dynamic Sorting within SQL Stored Procedures
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This approach keeps the sortable columns from being duplicated twice in the order by, and is a little more readable IMO:
SELECT
s.*
FROM
(SELECT
CASE @SortCol1
WHEN 'Foo' THEN t.Foo
WHEN 'Bar' THEN t.Bar
ELSE null
END as ...
How to show multiline text in a table cell
I want to show a paragraph from database into a table cell.
10 Answers
10
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How to speed up insertion performance in PostgreSQL
I am testing Postgres insertion performance. I have a table with one column with number as its data type. There is an index on it as well. I filled the database up using this query:
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Are there conventions on how to name resources?
...nge in time. So its completely normal that naming conventions that were suitable in the beginning will not be suitable after 2 years. And it's completely fine. You should not try to predict future. Just choose a convention and follow it. You will find if it is suitable for you and your project. If i...
Difference between 3NF and BCNF in simple terms (must be able to explain to an 8-year old)
...hree topping types:
one type of cheese
one type of meat
one type of vegetable
So we order two pizzas and choose the following toppings:
Pizza Topping Topping Type
-------- ---------- -------------
1 mozzarella cheese
1 pepperoni meat
1 olives vegetable
2 ...