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How do I automatically update a timestamp in PostgreSQL
... Says so in the Postgres documentation of the types. Varchar has extra CPU cycles to check for the constraint, which doesn't happen on TEXT.
– Rahly
Jun 21 '17 at 15:50
3...
Red black tree over avl tree
...ack tree.
AVL trees store the balance factor at each node. This takes O(N) extra space. However, if we know that the keys that will be inserted in the tree will always be greater than zero, we can use the sign bit of the keys to store the colour information of a red-black tree. Thus, in such cases r...
Convert a Map to a POJO
...o = mapper.convertValue(map, MyPojo.class);
No need to convert into JSON string or something else; direct conversion does much faster.
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Matplotlib tight_layout() doesn't take into account figure suptitle
...=24)
# Instead, do a hack by annotating the first axes with the desired
# string and set the positioning to 'figure fraction'.
fig.get_axes()[0].annotate('Long Suptitle', (0.5, 0.95),
xycoords='figure fraction', ha='center',
fontsize=24
...
Psql list all tables
...ate as "Collate",
d.datctype as "Ctype",
pg_catalog.array_to_string(d.datacl, E'\n') AS "Access privileges"
FROM pg_catalog.pg_database d
ORDER BY 1;
**************************
so you can see that psql is searching pg_catalog.pg_database when it gets a list of databases. Similarly, f...
How do I use prepared statements in SQlite in Android?
...t = db.compileStatement("INSERT INTO Country (code) VALUES (?)");
stmt.bindString(1, "US");
stmt.executeInsert();
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Can CSS force a line break after each word in an element?
...es a line-break wherever a line-break appears in the code, but ignores the extra whitespace (tabs and spaces etc.).
First, write your words on separate lines in your code:
<div>Short
Word</div>
Then apply the style to the element containing the words.
div { white-space: pre-line; }...
Best GWT widget library? [closed]
...se due to the dependency on some external AJAX library. This, as well, add extra size to your solution. Note, as well, that most of the widget libraries depend on one or more additional external components.
– IgorM
May 18 '09 at 20:09
...
What is the instanceof operator in JavaScript?
...an example taken directly from Mozilla's developer site:
var color1 = new String("green");
color1 instanceof String; // returns true
var color2 = "coral"; //no type specified
color2 instanceof String; // returns false (color2 is not a String object)
One thing worth mentioning is instanceof evalua...
Is there a difference between “throw” and “throw ex”?
...hrow doesn't - the original offender would be preserved.
static void Main(string[] args)
{
try
{
Method2();
}
catch (Exception ex)
{
Console.Write(ex.StackTrace.ToString());
Console.ReadKey();
}
}
private static void Method2()
{
try
{
...