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Is there an auto increment in sqlite?
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You get one for free, called ROWID. This is in every SQLite table whether you ask for it or not.
If you include a column of type INTEGER PRIMARY KEY, that column points at (is an alias for) the automatic ROWID column.
ROWID (by whatever name you call it)...
How can I get Maven to stop attempting to check for updates for artifacts from a certain group from
...king on a fairly big Maven project. We have probably around 70 or so individual artifacts, which are roughly split into two libraries of shared code and maybe ten applications which use them. All of these items live in the namespace com.mycompany.* .
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generate model using user:references vs user_id:integer
..., you can see that this is the case:
:001 > Micropost
=> Micropost(id: integer, user_id: integer, created_at: datetime, updated_at: datetime)
The second command adds a belongs_to :user relationship in your Micropost model whereas the first does not. When this relationship is specified, Ac...
How to sort with lambda in Python
...reverse=False)
so without the key=, the function you pass in will be considered a cmp function which takes 2 arguments.
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What's the difference between INNER JOIN, LEFT JOIN, RIGHT JOIN and FULL JOIN? [duplicate]
... is the top left picture not simply SELECT * FROM TableB;? Why is the top middle picture not SELECT * FROM A INTERSECT SELECT * FROM B ? etc
– onedaywhen
Sep 9 '11 at 10:41
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Difference between left join and right join in SQL Server [duplicate]
...ed completely interchangeable. Try however Table2 left join Table1 (or its identical pair, Table1 right join Table2) to see a difference. This query should give you more rows, since Table2 contains a row with an id which is not present in Table1.
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Split column at delimiter in data frame [duplicate]
...t some more magic to make it into a data.frame.
I added a "x|y" line to avoid ambiguities:
df <- data.frame(ID=11:13, FOO=c('a|b','b|c','x|y'))
foo <- data.frame(do.call('rbind', strsplit(as.character(df$FOO),'|',fixed=TRUE)))
Or, if you want to replace the columns in the existing data.fram...
Is there a “not in” operator in JavaScript for checking object properties?
... portion...
Just negate your condition, and you'll get the else logic inside the if:
if (!(id in tutorTimes)) { ... }
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How to do constructor chaining in C#
...ou use standard syntax (using this like a method) to pick the overload, inside the class:
class Foo
{
private int id;
private string name;
public Foo() : this(0, "")
{
}
public Foo(int id, string name)
{
this.id = id;
this.name = name;
}
pub...
How can you represent inheritance in a database?
...--+---------------------+----------+----------------+------------------+
| id | date_issued | type | vehicle_reg_no | property_address |
+------+---------------------+----------+----------------+------------------+
| 1 | 2010-08-20 12:00:00 | MOTOR | 01-A-04004 | NULL ...