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mysql> select CONCAT('My', 'S', 'QL');
-> 'MySQL'
mysql> select CONCAT('My', NULL, 'QL');
-> NULL
mysql> select CONCAT(14.3);
-> '14.3'
È磺update test set ID=concat(ID,'ABC');
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$db_name="new";
mysql_connect("localhost","root","123456");
mysql_select_db($db_name);
$tb=mysql_list_tables($db_name);
$sql="";
while($query=mysql_fetch_row($tb)){
$sql="";$table_sql="";
$sql.= get_table_fn($query[0]);
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using System;
using System.Collections.Generic;
using System.Text;
using System.Data;
using MySql.Data.MySqlClient;
namespace i_salesDAL
{
public class DBHelper
{
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mysql > OPTIMEZE TABLE foo;
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mysql > FLUSH PRIVILEGES;
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