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Odd behavior when Java converts int to byte?
...ned, and byte, short, int, and long are encoded in two's complement. (The char type is unsigned, and the concept of a sign is not applicable to boolean.)
In this number scheme the most significant bit specifies the sign of the number. If more bits are needed, the most significant bit ("MSB") is si...
How do you copy a record in a SQL table but swap out the unique id of the new row?
...
Try this:
insert into MyTable(field1, field2, id_backup)
select field1, field2, uniqueId from MyTable where uniqueId = @Id;
Any fields not specified should receive their default value (which is usually NULL when not defined).
...
Copy data into another table
...
If both tables are truly the same schema:
INSERT INTO newTable
SELECT * FROM oldTable
Otherwise, you'll have to specify the column names (the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema)...
How to best display in Terminal a MySQL SELECT returning too many fields?
...
Terminate the query with \G in place of ;. For example:
SELECT * FROM sometable\G
This query displays the rows vertically, like this:
*************************** 1. row ***************************
Host: localhost
Db: mydatabase1
...
What's wrong with this 1988 C code?
...ain() is also dated, it should be like something this.
int main(int argc, char** argv) {
...
return 0;
}
The compiler will assume an int return value for a function w/o one, and I'm sure the compiler/linker will work around the lack of declaration for argc/argv and the lack of return valu...
How to deal with SQL column names that look like SQL keywords?
...ange the name because I didn't make it.
Am I allowed to do something like SELECT from FROM TableName or is there a special syntax to avoid the SQL Server being confused?
...
Is there a combination of “LIKE” and “IN” in SQL?
...
An example table:
SQL> create table mytable (something)
2 as
3 select 'blabla' from dual union all
4 select 'notbla' from dual union all
5 select 'ofooof' from dual union all
6 select 'ofofof' from dual union all
7 select 'batzzz' from dual
8 /
Table created.
The origin...
Understanding colors on Android (six characters)
...ed as RGB or ARGB.
http://en.wikipedia.org/wiki/ARGB
In RGB you have two characters for every color (red, green, blue), and in ARGB you have two additional chars for the alpha channel.
So, if you have 8 characters, it's ARGB, with the first two characters specifying the alpha channel. If you remo...
How to create a MySQL hierarchical recursive query
... or self-joins.
MySQL 8+
with recursive cte (id, name, parent_id) as (
select id,
name,
parent_id
from products
where parent_id = 19
union all
select p.id,
p.name,
p.parent_id
from products p
inner join cte
...
Select mySQL based only on month and year
...
SELECT * FROM projects WHERE YEAR(Date) = 2011 AND MONTH(Date) = 5
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