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How to add a primary key to a MySQL table?
...mn, you can always add the primary key:
ALTER TABLE goods ADD PRIMARY KEY(id)
As to why your script wasn't working, you need to specify PRIMARY KEY, not just the word PRIMARY:
alter table goods add column `id` int(10) unsigned primary KEY AUTO_INCREMENT;
...
Getting root permissions on a file inside of vi? [closed]
...ke prompt that appears after running the :! command.
exec[ute] executes a string as a command. We can't just run :write because it won't process the necessary function call.
! represents the :! command: the only command that :write accepts. Normally, :write accepts a file path to which to write....
How do I change the formatting of numbers on an axis with ggplot?
...n Diggs.
fancy_scientific <- function(l) {
# turn in to character string in scientific notation
l <- format(l, scientific = TRUE)
# quote the part before the exponent to keep all the digits
l <- gsub("^(.*)e", "'\\1'e", l)
# turn the 'e+' into plotmath format
...
CSS styling in Django forms
...e'> in Django
class MyForm(forms.Form):
myfield = forms.CharField(widget=forms.TextInput(attrs={'class' : 'myfieldclass'}))
or
class MyForm(forms.ModelForm):
class Meta:
model = MyModel
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwa...
Initialize class fields in constructor or at declaration?
...eed to use some other logic.
public class AdminTeam
{
private List<string> usernames;
public AdminTeam()
{
usernames = new List<string>() {"usernameA", "usernameB"};
}
}
or
public class AdminTeam
{
private List<string> usernames;
public AdminT...
Getting a better understanding of callback functions in JavaScript
...
Why do you cast callback to string and then check its type? Will this enhance performance? This is like checking the type, checking if the converted boolean returns true and then checking its type again and testing it against the string... Could you exp...
JPA and Hibernate - Criteria vs. JPQL or HQL
...afer to the programmer, diminishing coding errors - compilation on the HQL string is not validated.
– nuno
Jul 31 '14 at 8:37
...
INSERT IF NOT EXISTS ELSE UPDATE?
...ang_conflict.html.
You want something like:
insert or replace into Book (ID, Name, TypeID, Level, Seen) values
((select ID from Book where Name = "SearchName"), "SearchName", ...);
Note that any field not in the insert list will be set to NULL if the row already exists in the table. This is why ...
Rails auto-assigning id that already exists
...
Rails is probably using the built-in PostgreSQL sequence. The idea of a sequence is that it is only used once.
The simplest solution is to set the sequence for your company.id column to the highest value in the table with a query like this:
SELECT setval('company_id_seq', (SELECT max(...
How to explicitly discard an out argument?
...the method in another method that does the out parameter for you like so:
String Other_MakeMyCall(String inputParams)
{
String messages;
return MakeMyCall(inputParams, out messages);
}
Then you can call Other_MakeMyCall without having to fiddle with out parameters you don't need.
...