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Border around tr element doesn't show?
... not render borders on tr , but it renders the border if the selector is table tr td .
1 Answer
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How do I view the SQLite database on an Android device? [duplicate]
...le Java activity file; just add it to your source folder.
You can view the tables in your app database, update, delete, insert rows to you table. Everything from inside your app.
When the development is done remove the Java file from your src folder. That's it.
You can view the 5 minute demo, Data...
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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B-Tree vs Hash Table
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You can only access elements by their primary key in a hashtable.
This is faster than with a tree algorithm (O(1) instead of log(n)), but you cannot select ranges (everything in between x and y).
Tree algorithms support this in Log(n) whereas hash indexes can result in a full table s...
What's the best manner of implementing a social activity stream? [closed]
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I have created such system and I took this approach:
Database table with the following columns: id, userId, type, data, time.
userId is the user who generated the activity
type is the type of the activity (i.e. Wrote blog post, added photo, commented on user's photo)
data is a seriali...
SQL ON DELETE CASCADE, Which Way Does the Deletion Occur?
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Cascade will work when you delete something on table Courses. Any record on table BookCourses that has reference to table Courses will be deleted automatically.
But when you try to delete on table BookCourses only the table itself is affected and not on the Courses
foll...
Count(*) vs Count(1) - SQL Server
...uld be evaluated as per ANSI
b) Otherwise, let TX be the single-column table that is the
result of applying the <value expression> to each row of T
and eliminating null values. If one or more null values are
eliminated, then a completion cond...
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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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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select into in mysql
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Use the CREATE TABLE SELECT syntax.
http://dev.mysql.com/doc/refman/5.0/en/create-table-select.html
CREATE TABLE new_tbl SELECT * FROM orig_tbl;
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