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PostgreSQL: Show tables in PostgreSQL
...a:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
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How can I access my localhost from my Android device?
...n be done with the following:
Open Settings
Go to Network & Internet
Select WiFi in the left menu
Tap on the name of the connected WiFi
Set the Network Profile of the network to be Private
If you are having an issue, it is most likely to do with Windows Firewall.
Open Control Panel
Go to W...
SQL JOIN - WHERE clause vs. ON clause
...
They are not the same thing.
Consider these queries:
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will re...
What is the in a .vimrc file?
...or example, if you find yourself frequently deleting exactly 3 words and 7 characters, you might find it convenient to map a command via nmap <leader>d 3dw7x so that pressing the leader key followed by d will delete 3 words and 7 characters. Because it uses the leader key as a prefix, you can ...
How to use SharedPreferences in Android to store, fetch and edit values [closed]
...);
editor.putString("text", mSaved.getText().toString());
editor.putInt("selection-start", mSaved.getSelectionStart());
editor.putInt("selection-end", mSaved.getSelectionEnd());
editor.apply();
To retrieve data from sharedpreference
SharedPreferences prefs = getPreferences(MODE_PRIVATE);
Str...
Sql query to insert datetime in SQL Server
...clare @LangID smallint
declare @Alias sysname
declare @MaxLangID smallint
select @MaxLangID = max(langid) from sys.syslanguages
set @LangID = 0
while @LangID <= @MaxLangID
begin
select @Alias = alias
from sys.syslanguages
where langid = @LangID
if @Alias is not null
begin...
Getting jQuery to recognise .change() in IE
..., in my testing this is not correct and jquery's click does trigger when i select the next radio button using arrow keys. (vista, ie7)
– svandragt
Nov 7 '08 at 13:51
1
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SQL standard to escape column names?
...
For MySQL, use back ticks `.
For instance:
SELECT `column`, `column2` FROM `table`
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What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
... using Standard SQL.
An obvious omission is the equivalent using EXCEPT:
SELECT a FROM table1
EXCEPT
SELECT a FROM table2
Note in Oracle you need to use the MINUS operator (arguably a better name):
SELECT a FROM table1
MINUS
SELECT a FROM table2
Speaking of proprietary syntax, there may also ...
How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...