大约有 40,000 项符合查询结果（耗时：0.0510秒） [XML]
LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method ca
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It's true this method would be inefficient for any table that contains more than one record, meaning all tables in existence :-). However, this answer did help me today because I was doing a .Select projection that included toString() so calling .ToList() before hand had no ...
UITableView Cell selected Color?
I have created a custom UITableViewCell . The table view is showing data fine. What I am stuck in is when user touches cell of tableview, then I want to show the background color of the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothi...
How can I define a composite primary key in SQL?
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Just for clarification: a table can have at most one primary key. A primary key consists of one or more columns (from that table). If a primary key consists of two or more columns it is called a composite primary key. It is defined as follows:
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invalid byte sequence for encoding “UTF8”
... trying to import some data into my database. So I've created a temporary table,
20 Answers
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What's the fastest way to do a bulk insert into Postgres?
...e as CSV formatted mapping in PG query statement's. You can try for Big Table?
– Elyor
Sep 9 '14 at 2:03
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MySQL ON DUPLICATE KEY - last insert id?
...on to that MySQL function.
From the MySQL documentation example:
If a table contains an AUTO_INCREMENT column and INSERT ... UPDATE inserts a row, the LAST_INSERT_ID() function returns the AUTO_INCREMENT value. If the statement updates a row instead, LAST_INSERT_ID() is not meaningful. However,...
Add a column to a table, if it does not already exist
I want to write a query for MS SQL Server that adds a column into a table. But I don't want any error display, when I run/execute the following query.
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Grant **all** privileges on database
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@Romain you are not really bringing alot to the table here - i don't name my users myuser - the questioner was simply using a username as an example - i used the same example username for consistency.
– diagonalbatman
Feb 16 '11 at 13...
Is there any good dynamic SQL builder library in Java? [closed]
... concept of code generation, where meta classes are generated for database tables and fields. This facilitates a nice, clean DSL but it faces a problem when trying to create queries for databases that are only known at runtime, like in the OP's example above. While jOOQ supports a String based appro...
How to select date from datetime column?
...f operators in an indexed column is high. These are some test results on a table with 1,176,000 rows:
using datetime LIKE '2009-10-20%' => 2931ms
using datetime >= '2009-10-20 00:00:00' AND datetime <= '2009-10-20 23:59:59' => 168ms
When doing a second call over the same query the di...