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How to find a table having a specific column in postgresql
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you can query system catalogs:
select c.relname
from pg_class as c
inner join pg_attribute as a on a.attrelid = c.oid
where a.attname = <column name> and c.relkind = 'r'
sql fiddle demo
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How to use GROUP BY to concatenate strings in MySQL?
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SELECT id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string res...
Python function overloading
...working with languages that can discriminate data types at
compile-time, selecting among the alternatives can occur at
compile-time. The act of creating such alternative functions for
compile-time selection is usually referred to as overloading a
function. (Wikipedia)
Python is a dynamical...
What is syntax for selector in CSS for next element?
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This is called the adjacent sibling selector, and it is represented by a plus sign...
h1.hc-reform + p {
clear:both;
}
Note: this is not supported in IE6 or older.
share
|...
What specific productivity gains do Vim/Emacs provide over GUI text editors?
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Yeah, the mouse can be a timesaver for selecting areas of text, or moving the cursor to a specific spot in a large amount of text. Otherwise, it's a waste.
– T.E.D.
Jul 7 '09 at 14:27
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How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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nvarchar(max) vs NText
...was instant.
I ran the following to find all columns needing conversion:
SELECT concat('ALTER TABLE dbo.[', table_name, '] ALTER COLUMN [', column_name, '] VARCHAR(MAX)'), table_name, column_name
FROM information_schema.columns where data_type = 'TEXT' order by table_name, column_name
SELECT conc...
How to find and turn on USB debugging mode on Nexus 4
...phone then tap Build number 7 times. Tap the Back icon to Settings then select System > Advanced > Developer options.
Ensure that the Developer options switch (upper-right) is turned on .
Tap USB debugging to turn on or off .
If prompted with 'Allow USB debugging?', tap OK to ...
Install MySQL on Ubuntu without a password prompt
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sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...
Return number of rows affected by UPDATE statements
...NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3 INTEGER
DECLARE @RowCount4 INTEGER
UPDATE Table1 Set Column = 0 WHERE Column IS NULL
SEL...