数据库备份SQL查询 [英] Database backup SQL Query

问题描述

我需要以插入语句的形式从数据库中获取数据以进行备份

I need to fetch data from database for backup in the form of insert statements

我需要在c#中单击一个按钮来执行此操作.因此，我认为使用sql查询或存储过程而不是mysqldump更为合适.

I need to do it on a button click in c#. So i think an sql query or stored procedure will be appropriate to do this, rather than mysqldump.

第二，所有表格都需要它们.而不是写表和列的名称.应该从information_schema中获取它们，因为无需针对不同的scema更改查询.

Secondly I need them for all tables. Instead of writing table and column names. They should be fetched from information_schema, because the query will not need to be changed for different scema

如果已经存在解决方案，请指导我.

If there already exists a solution, please guide me.

更新:我已经准备了一种解决方案，它已经发布，仍在寻找更好的解决方案.

Update : I have prepared a solution, it is posted, still looking for the better one.

推荐答案

获取数据整个数据库-SqlFiddle演示

仅获取一个表的数据--SqlFiddle演示

To get Data of whole database - SqlFiddle Demo

To get data of only one table - - SqlFiddle Demo

我提出了一个复杂但可以接受的解决方案. 但需要改进.

I have made a complex but acceptable solution. But needs improvement.

这是一个复杂的过程，具有复杂的编码，尤其是查询，该查询通过group_concat将所有列的所有行提取到单个结果中，并使用复杂的级联进行格式化.

This is a complex procedure with complex coding especially the query which fetches all rows of all columns into a single result by group_concat and formats with a complex concatenation.

需要简化，高效并且在所有情况下都可以工作.

Need it simplified, efficient and working in all scenarios.

我的解决方案的一些详细信息:以下是重要的部分，其他仅是条件/循环(我不方便使用文档，它也需要时间和建议，有人可能会帮助我设置格式并的改进，给您带来的不便，我们深表歉意.但是，如果您和我有任何帮助，我将很高兴.)

Some details of my solution : Following is the important part, other is just conditions/Looping (I am not handy with documentation also it needs time and suggestions, someone might help me in its formatting and improvement, Sorry for any inconvenience, however I will be glad for any help from you and me)

注意:group_concat(yourColumn分隔符'--anySeparator--')将列的所有行合并为一个，这样行被--anySeparator--分隔

Note: group_concat(yourColumn separator ' --anySeparator-- ') is merging all rows of your column as one such that Rows are separated by --anySeparator--

select group_concat(column_name separator '`,`') into @cns1 from
information_schema.columns where table_schema=dn and table_name=@tn;

1:column_names作为单个值得到，

1 : column_names are got as a single value separated by

`,` => @cs1 = id`,`ename`,`did

select group_concat(column_name separator '`,"\',\'",`') into @cns2
from information_schema.columns where table_schema=dn and table_name=@tn;

2:column_names作为单个值得到，

2 : column_names are got as a single value separated by

`','` => @cn2  = id`','`ename`','`did

set @cns1=concat("`",@cns1,"`");    set @cns2=concat("`",@cns2,"`");

3:缺少字母(`)放在列名的开头和结尾

3: Missing letter (`) is put at beginning and end of Column names

set @res=concat(@res," insert into ",@tn,"(",@cns1,") values ('");

4:只需使res= " insert into emp(`id` ,`ename` ,`did` ) values("在这里您可以看到为什么要放置分隔符(实现了MySql格式)

4: Simply makes res= " insert into emp(`id` , `ename` ,`did` ) values(" Here you can see why have I put separators (MySql Formatting is achieved)

set @temp := '';
set @q := concat("select group_concat(concat(",@cns2,") separator \"'),('\")
 from ",dn,".",@tn, " into @temp");

以上是最关键的语句:它从表中获取所有数据行作为单列的行，并且进一步合并这些行，并用'),('

Above is the most crucial statement It gets all data rows from table as rows of a single column and further these rows are merged being separated by '),('

5.1 concat(",@cns2,")在一列中获取所有列的值.

5.1 concat(",@cns2,") gets values of all columns in a single one.

5.2现在最外面的连拍之后@q是

5.2 After outer most concat now @q is

 @q = "select group_concat(`id`','`ename`','`,did` separator '),(' from 
mydb.emp into @temp";

5.3:group_concat将合并的列的所有行合并为一个值. 列值将通过@ cns2中存在的分隔符进行连接，而行级别的连接将使用'),('

5.3 : group_concat will merge all rows of that combined column into one value. Columns values will be joined through separators existing in @cns2 and rows level joining will be with '),('

prepare s1 from @q;
execute s1;deallocate prepare s1;
set @res = concat(@res,@temp,");");    

@q被执行

set @res = concat(@res,@temp,");");

6:我们将得到结果

 res was = insert into emp(`id`,`ename`,`did`) values ('
@temp = 1','e1','4'),('2','e2','4'),
('3','e3','2'),('4','e4','4'),('5','e5','3

在@res = concat(@res,@temp,");");之后，我们得到了

 insert into emp(`id`,`ename`,`did`) values ('1','e1','4'),('2','e2','4'),
('3','e3','2'),('4','e4','4'),('5','e5','3);

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