大约有 37,000 项符合查询结果（耗时：0.0612秒） [XML]
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:
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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 =
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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
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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>&...
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.
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PadLeft function in T-SQL
I have the following table A:
17 Answers
17
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MySQL: What's the difference between float and double?
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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
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How do I view the full content of a text or varchar(MAX) column in SQL Server 2008 Management Studio
... this live SQL Server 2008 (build 10.0.1600) database, there's an Events table, which contains a text column named Details . (Yes, I realize this should actually be a varchar(MAX) column, but whoever set this database up did not do it that way.)
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efficient way to implement paging
...mehow direct paging in the SQL engine.
Giving you an example, I have a db table called mtcity and I wrote the following query (work as well with linq to entities):
using (DataClasses1DataContext c = new DataClasses1DataContext())
{
var query = (from MtCity2 c1 in c.MtCity2s
sel...