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How do I query between two dates using MySQL?
...ember 29 2010 and January 30 2010). Try reversing the order of the dates:
SELECT *
FROM `objects`
WHERE (date_field BETWEEN '2010-01-30 14:15:55' AND '2010-09-29 10:15:55')
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Cast int to varchar
...datatype, there is no varchar datatype that you can cast/convert data to:
select CAST(id as CHAR(50)) as col1
from t9;
select CONVERT(id, CHAR(50)) as colI1
from t9;
See the following SQL — in action — over at SQL Fiddle:
/*! Build Schema */
create table t9 (id INT, name VARCHAR(55));
ins...
Duplicating a MySQL table, indices, and data
...ese 2 queries:
CREATE TABLE newtable LIKE oldtable;
INSERT INTO newtable SELECT * FROM oldtable;
To copy just structure and data use this one:
CREATE TABLE tbl_new AS SELECT * FROM tbl_old;
I've asked this before:
Copy a MySQL table including indexes
...
How can I select random files from a directory in bash?
I have a directory with about 2000 files. How can I select a random sample of N files through using either a bash script or a list of piped commands?
...
How do I get IntelliJ IDEA to display directories?
...correctly. Make sure the "Content Root" is correct.
Click on the project
Select "File"->"Project Structure"
Select "modules" from the left column, and select a module.
On the sources tab you will see the current "Content Root" along with a button to add a new content root.
Make sure that con...
PostgreSQL - fetch the row which has the Max value for a column
...sted index lookup into lives - on my machine
-- the latter query plan was selected given my memory settings and
-- histogram
SELECT
l1.*
FROM
lives AS l1
INNER JOIN (
SELECT
usr_id,
MAX(time_stamp) AS time_stamp_max
FROM
lives
GROUP BY
usr_id
) AS l2
...
XPath: select text node
... XML:
<node>Text1<subnode/>text2</node>
How do I select either the first or
the second text node via XPath?
Use:
/node/text()
This selects all text-node children of the top element (named "node") of the XML document.
/node/text()[1]
This selects the first text-nod...
how to implement regions/code collapse in javascript
....Collections
Public Module JsMacros
Sub OutlineRegions()
Dim selection As EnvDTE.TextSelection = DTE.ActiveDocument.Selection
Const REGION_START As String = "//#region"
Const REGION_END As String = "//#endregion"
selection.SelectAll()
Dim text As Strin...
DropDownList in MVC 4 with Razor
...
@{
List<SelectListItem> listItems= new List<SelectListItem>();
listItems.Add(new SelectListItem
{
Text = "Exemplo1",
Value = "Exemplo1"
});
listItems.Add(new SelectListItem
{...
How to drop columns by name in a data frame
..."z","u"))]
x y
1 1 2
2 2 3
3 3 4
4 4 5
5 5 6
Or, much simpler, use the select argument of the subset function : you can then use the - operator directly on a vector of column names, and you can even omit the quotes around the names !
R> subset(df, select=-c(z,u))
x y
1 1 2
2 2 3
3 3 4
4 4 ...