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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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Want to find records with no associated records in Rails
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Just imagine you have 10000000 records in friends table. What about performance in that case?
– goodniceweb
Dec 20 '16 at 14:51
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How to join (merge) data frames (inner, outer, left, right)
...f performance is a major issue for you, you should also look into the data.table package - that's a whole new set of join syntax, but it's radically faster than anything we're talking about here.
– Matt Parker
Feb 12 '13 at 16:22
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
I have created my tables in my SQLiteOpenHelper onCreate() but receive
15 Answers
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EF Code First “Invalid column name 'Discriminator'” but no inheritance
I have a table in my database called SEntries (see below the CREATE TABLE statement). It has a primary key, a couple of foreign keys and nothing special about it. I have many tables in my database similar to that one, but for some reason, this table ended up with a "Discriminator" column on the EF P...
How to disable scrolling in UITableView table when the content fits on the screen
I have a few (grouped style) tables in my iphone app (only on part of the screen and added with Interface Builder though, not subclassed from UITableViewController ) that 80% of the time are small and will fit on the screen. When the table fits on the screen, I'd like to disable scrolling, to ma...
Resizing UITableView to fit content
...ve a question in a UILabel and a multiple choice answers displayed in UITableView , each row showing a multiple choice. Questions and answers will vary, so I need this UITableView to be dynamic in height.
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
Let's say I have the following data.table in R :
3 Answers
3
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Relational Database Design Patterns? [closed]
...elationships using a foreign key.
Many-to-Many relationships with a bridge table.
Optional one-to-one relationships managed with NULLs in the FK column.
Star-Schema: Dimension and Fact, OLAP design.
Fully normalized OLTP design.
Multiple indexed search columns in a dimension.
"Lookup table" that con...
With MySQL, how can I generate a column containing the record index in a table?
...itialization without requiring a separate SET command.
Test case:
CREATE TABLE league_girl (position int, username varchar(10), score int);
INSERT INTO league_girl VALUES (1, 'a', 10);
INSERT INTO league_girl VALUES (2, 'b', 25);
INSERT INTO league_girl VALUES (3, 'c', 75);
INSERT INTO league_girl...