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Adding 'serial' to existing column in Postgres
...int, b text);
CREATE TABLE bar (a serial, b text);
INSERT INTO foo (a, b) SELECT i, 'foo ' || i::text FROM generate_series(1, 5) i;
INSERT INTO bar (b) SELECT 'bar ' || i::text FROM generate_series(1, 5) i;
-- blocks of commands to turn foo into bar
CREATE SEQUENCE foo_a_seq;
ALTER TABLE foo ALTER...
how to use ng-option to set default value of select element
I've seen the documentation of the Angular select directive here: http://docs.angularjs.org/api/ng.directive:select .
I can't figure how to set the default value. This is confusing:
...
Can PHP PDO Statements accept the table or column name as parameter?
... case 1:
$tbl = 'users';
break;
}
$sql = "SELECT * FROM $tbl";
}
By leaving no default case or using a default case that returns an error message you ensure that only values that you want used get used.
...
Using the HTML5 “required” attribute for a group of checkboxes?
...ng is jQuery script, which disables further validation check if any one is selected. Select using name element.
$cbx_group = $("input:checkbox[name='option[]']");
$cbx_group = $("input:checkbox[id^='option-']"); // name is not always helpful ;)
$cbx_group.prop('required', true);
if($cbx_group.is("...
One-liner to recursively list directories in Ruby?
...elsif child.directory?
rec_path(child, file) + [child]
end
end.select { |x| x }.flatten(1)
end
# only directories
rec_path(Pathname.new(dir), false)
# directories and normal files
rec_path(Pathname.new(dir), true)
...
Should I use the datetime or timestamp data type in MySQL?
...o with the native format. You can do calculations within MySQL that way
("SELECT DATE_ADD(my_datetime, INTERVAL 1 DAY)") and it is simple to change the format of the value to a UNIX timestamp ("SELECT UNIX_TIMESTAMP(my_datetime)") when you query the record if you want to operate on it with PHP.
...
Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
...
What is a reasonable length limit on person “Name” fields?
...put their information, including name. I gave the name field a limit of 50 characters to coincide with my database table where the field is varchar(50), but then I started to wonder.
...
Using “like” wildcard in prepared statement
...place("[", "![");
PreparedStatement pstmt = con.prepareStatement(
"SELECT * FROM analysis WHERE notes LIKE ? ESCAPE '!'");
pstmt.setString(1, notes + "%");
or a suffix-match:
pstmt.setString(1, "%" + notes);
or a global match:
pstmt.setString(1, "%" + notes + "%");
...
fatal error: malformed or corrupted AST file - Xcode
...olved the issue for me. In Xcode, go to Window->Organizer->Projects, select your project, and press the "Delete..." button next to "Derived data".
If this doesn't work, you can try to do a Product->Clean (Cmd+Shift+k).
...