大约有 37,000 项符合查询结果（耗时：0.0419秒） [XML]
Count work days between two dates
...their post, I just added holidays to the function (This assumes you have a table "tblHolidays" with a datetime field "HolDate".
--Changing current database to the Master database allows function to be shared by everyone.
USE MASTER
GO
--If the function already exists, drop it.
IF EXISTS
(
SEL...
MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
...
How to convert numbers between hexadecimal and decimal
...on from hex to decimal number, you can use the approach with pre-populated table of hex-to-decimal values.
Here is the code that illustrates that idea. My performance tests showed that it can be 20%-40% faster than Convert.ToInt32(...):
class TableConvert
{
static sbyte[] unhex_table =
...
Doctrine and composite unique keys
...Mapping\UniqueConstraint;
/**
* Common\Model\Entity\VideoSettings
*
* @Table(name="video_settings",
* uniqueConstraints={
* @UniqueConstraint(name="video_unique",
* columns={"video_dimension", "video_bitrate"})
* }
* )
* @Entity
*/
See @UniqueConstraint
...
Join vs. sub-query
...and query-specific.
Historically, explicit joins usually win, hence the established wisdom that joins are better, but optimisers are getting better all the time, and so I prefer to write queries first in a logically coherent way, and then restructure if performance constraints warrant this.
...
Are PostgreSQL column names case-sensitive?
I have a db table say, persons in Postgres handed down by another team that has a column name say, "first_Name" . Now am trying to use PG commander to query this table on this column-name.
...
PadLeft function in T-SQL
I have the following table A:
17 Answers
17
...
How may I align text to the left and text to the right in the same line?
...untime that it looks bad.
What I like to do is simply create a single row table and apply the right float on the second cell. No need to apply a left-align on the first, that happens by default. This handles overlap perfectly by word-wrapping.
HTML
<table style="width: 100%;">
<tr>&...
MySQL: What's the difference between float and double?
...
Perhaps this example could explain.
CREATE TABLE `test`(`fla` FLOAT,`flb` FLOAT,`dba` DOUBLE(10,2),`dbb` DOUBLE(10,2));
We have a table like this:
+-------+-------------+
| Field | Type |
+-------+-------------+
| fla | float |
| flb | float |...
How to select only the records with the highest date in LINQ
I have a table, 'lasttraces', with the following fields.
5 Answers
5
...