大约有 40,000 项符合查询结果（耗时：0.0325秒） [XML]
Manually map column names with class properties
...
This works fine:
var sql = @"select top 1 person_id PersonId, first_name FirstName, last_name LastName from Person";
using (var conn = ConnectionFactory.GetConnection())
{
var person = conn.Query<Person>(sql).ToList();
return person;
}
Da...
Code Golf - π day
... area="{@area}"/>
</xsl:variable>
<xsl:apply-templates select="msxsl:node-set($next)"/>
</xsl:template>
<!-- End of the line?-->
<xsl:template match="s[@x &gt; @R]">
<xsl:variable name="next">
<!-- Go to next line.-->
&l...
How do MySQL indexes work?
...be faster to go through the pages one by one (in a database, this is "poor selectivity").
For a 10-page book, it makes no sense to make an index, as you may end up with a 10-page book prefixed by a 5-page index, which is just silly - just scan the 10 pages and be done with it.
The index also needs t...
How to add column if not exists on PostgreSQL?
...s, _col text, _type regtype)
RETURNS bool AS
$func$
BEGIN
IF EXISTS (SELECT 1 FROM pg_attribute
WHERE attrelid = _tbl
AND attname = _col
AND NOT attisdropped) THEN
RETURN FALSE;
ELSE
EXECUTE format('ALTER TABLE %s ADD COLUMN %I %s...
The object cannot be deleted because it was not found in the ObjectStateManager
... var project = context.Projects
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Profession)))
.Include(p => p.Reports.Select(q => q.Issues.Select(r => r.Room)))
.SingleOrDefault(x => x.Id == id);
return proje...
MySQL with Node.js
....log('connected as id ' + connection.threadId);
connection.query("select * from user",function(err,rows){
connection.release();
if(!err) {
res.json(rows);
}
});
connection.on('error', function(err) {
...
Checkbox for nullable boolean
...ents your null, whatever the semantics of null means. You could use a <select><option> drop down list to save real estate, but the user has to click twice and the choices aren't nearly as instantaneously clear.
1 0 null
True False Not Set
Yes No Undecided
Male Fema...
PostgreSQL “DESCRIBE TABLE”
... 'table' or \ds 'sequence' and so on)
The SQL standard way, as shown here:
select column_name, data_type, character_maximum_length, column_default, is_nullable
from INFORMATION_SCHEMA.COLUMNS where table_name = '<name of table>';
It's supported by many db engines.
...
创建增量同步Oracle物化视图问题 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
..._tablename refresh fast on demand start with sysdate next sysdate+1/288 as select * from T_tablename@dblink_name;”。
现在，数据库A上此表的主键约束因主键字段值重复而被disable了，在第三个数据库C上新建这个物化视图却失败，说：“ORA-12014: 表 'T_MV_TE...
Formatting code in Notepad++
...X -> HTML Tidy -> Tidy: Reindent XML
Remember to have the HTML code selected before you do this.
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