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SQL select join: is it possible to prefix all columns as 'prefix.*'?
... you want to know with regard to a specific dbms product. Then you need to identify it. But I imagine the most likely answer is that you'll get back something like "a.id, b.id" since that's how you'd need to identify the columns in your SQL expression. And the easiest way to find out what the defaul...
Places where JavaBeans are used?
...ser implements java.io.Serializable {
// Properties.
private Long id;
private String name;
private Date birthdate;
// Getters.
public Long getId() { return id; }
public String getName() { return name; }
public Date getBirthdate() { return birthdate; }
// Setter...
PostgreSQL - max number of parameters in “IN” clause?
...using Posgresql's JDBC driver 9.1.
This is a test of "delete from x where id in (... 100k values...)" with the postgresql jdbc driver:
Caused by: java.io.IOException: Tried to send an out-of-range integer as a 2-byte value: 100000
at org.postgresql.core.PGStream.SendInteger2(PGStream.java:201)...
How to use Servlets and Ajax?
...n", function() { // When HTML DOM "click" event is invoked on element with ID "somebutton", execute the following function...
$.get("someservlet", function(responseText) { // Execute Ajax GET request on URL of "someservlet" and execute the following function with Ajax response text...
What's the difference between Spring Data's MongoTemplate and MongoRepository?
...out of the custom name. yourCustomMethod(). It will say "your" is not a valid field in the domain class. I followed the manual and also double checked how you are doing it the spring-data-jpa-examples. No luck. spring-data always tries to auto-generate as soon I extend the custom interface to the re...
How can I find out what FOREIGN KEY constraint references a table in SQL Server?
...
Here it is:
SELECT
OBJECT_NAME(f.parent_object_id) TableName,
COL_NAME(fc.parent_object_id,fc.parent_column_id) ColName
FROM
sys.foreign_keys AS f
INNER JOIN
sys.foreign_key_columns AS fc
ON f.OBJECT_ID = fc.constraint_object_id
INNER JOIN
sys.tables...
Get content uri from file path in android
...th the above solutions returns: 1. file:///storage/emulated/0/DCIM/Camera/VID_20140312_171146.mp4 2. /storage/emulated/0/DCIM/Camera/VID_20140312_171146.mp4 But what i was looking for is something different. I need the content:// format URI. The answer from Jinal seems to work perfect
...
CSS – why doesn’t percentage height work? [duplicate]
... percentage value for height doesn’t work but a percentage value for width does?
6 Answers
...
Laravel Migration Change to Make a Column Nullable
I created a migration with unsigned user_id . How can I edit user_id in a new migration to also make it nullable() ?
9 ...
Pandas get topmost n records within each group
...
Did you try df.groupby('id').head(2)
Ouput generated:
>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
...