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What is the difference between JOIN and UNION?
...t -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 rows in set (0.00 sec)
similary trivial example of JOIN:
mysql> SELECT * FROM
-> (SELECT 23 AS bah...
Changing the selected option of an HTML Select element
In my HTML, I have a <select> with three <option> elements. I want to use jQuery to check each option's value against a Javascript var . If one matches, I want to set the selected attribute of that option. How would I do that?
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typecast string to integer - Postgres
...ur value is an empty string, you can use NULLIF to replace it for a NULL:
SELECT
NULLIF(your_value, '')::int
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How to get the caret column (not pixels) position in a textarea, in characters, from the start?
...refox, Safari (and other Gecko based browsers) you can easily use textarea.selectionStart, but for IE that doesn't work, so you will have to do something like this:
function getCaret(node) {
if (node.selectionStart) {
return node.selectionStart;
} else if (!document.selection) {
return ...
How to generate the “create table” sql statement for an existing table in postgreSQL
... text;
column_record record;
BEGIN
FOR column_record IN
SELECT
b.nspname as schema_name,
b.relname as table_name,
a.attname as column_name,
pg_catalog.format_type(a.atttypid, a.atttypmod) as column_type,
CASE WHEN
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Combining “LIKE” and “IN” for SQL Server [duplicate]
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Effectively, the IN statement creates a series of OR statements... so
SELECT * FROM table WHERE column IN (1, 2, 3)
Is effectively
SELECT * FROM table WHERE column = 1 OR column = 2 OR column = 3
And sadly, that is the route you'll have to take with your LIKE statements
SELECT * FROM tabl...
What is the best way to auto-generate INSERT statements for a SQL Server table?
...2008:
Right-click on the database and go to Tasks > Generate Scripts.
Select the tables (or objects) that you want to generate the script against.
Go to Set scripting options tab and click on the Advanced button.
In the General category, go to Type of data to script
There are 3 options: Schema ...
How do I calculate tables size in Oracle
...BLE_NAME FORMAT A32
COLUMN OBJECT_NAME FORMAT A32
COLUMN OWNER FORMAT A10
SELECT
owner,
table_name,
TRUNC(sum(bytes)/1024/1024) Meg,
ROUND( ratio_to_report( sum(bytes) ) over () * 100) Percent
FROM
(SELECT segment_name table_name, owner, bytes
FROM dba_segments
WHERE segment_type IN...
xcode-select active developer directory error
...red node-gyp ... but could be triggered by anything which requires xcode-select .
23 Answers
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jQuery get value of selected radio button
The problem statement is simple. I need to see if user has selected a radio button from a radio group. Every radio button in the group share same id.
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