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A beginner's guide to SQL database design [closed]
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Experience counts for a lot, but in terms of table design you can learn a lot from how ORMs like Hibernate and Grails operate to see why they do things. In addition:
Keep different types of data separate - don't store addresses in your order table, link to an address ...
Escape single quote character for use in an SQLite query
I wrote the database schema (only one table so far), and the INSERT statements for that table in one file. Then I created the database as follows:
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Best way to store password in database [closed]
...gets a hold of your database, they can still use what are known as rainbow tables to be able to "decrypt" the password (at least those that show up in the rainbow table). To get around this, developers add a salt to passwords which, when properly done, makes rainbow attacks simply infeasible to do. ...
Center image in table td in CSS
I've been trying to align an image to the center of the table td. It worked with setting margin-left to a specific value but it also increased the size of td too and that isn't exactly what I wanted
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Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements. Previ
I have an Insert stored procedure which will feed data to Table1 and get the Column1 value from Table1 and call the second stored procedure which will feed the Table2.
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data.frame rows to a list
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@AaronMcDaid Or data.table::rbindlist(). If your original data frame was large, the speed gains will be significant.
– Empiromancer
Jul 12 '16 at 22:04
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Using arrays or std::vectors in C++, what's the performance gap?
...ong. The standard forbids exponential growth: § 23.2.3 paragraph 16 says "Table 101 lists operations that are provided for some types of sequence containers but not others. An implementation shall provide these operations for all container types shown in the “container” column, and shall implem...
SQL join: selecting the last records in a one-to-many relationship
Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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Force R not to use exponential notation (e.g. e+10)?
...file auto-executes it. This is useful for e.g. default package loads, data.table configuration, environment etc. Again, that config can run to a page of settings, and there's zero chance you'll remember those and their syntax and type them in
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How to remove leading and trailing whitespace in a MySQL field?
I have a table with two fields (countries and ISO codes):
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