blocks|key|1945098|text|删除基础数据库表中的所有记录(这将取决于数据库)并只调用一次刷新。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1945099|如果必须通过TFdTable完成，请使用BeginBatch，执行删除(不刷新)、EndBatch，然后才刷新。|1945100|+mytable.BeginBatch;
+for+i+:=+mytable.RecordCount+-+1+downto+0+do
+begin
++++mytable.Delete;
+end;
+mytable.EndBatch;
+mytable.Refresh;|code-block|syntax|javascript|1945101|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Remove all the records in the underlying database table (the best way to do that will depend on the database) and call refresh just once. 

If you must do it via TFdTable, use BeginBatch, do your deletes (without refresh), EndBatch and only then Refresh.

<pre><code> mytable.BeginBatch;
 for i := mytable.RecordCount - 1 downto 0 do
 begin
 mytable.Delete;
 end;
 mytable.EndBatch;
 mytable.Refresh;
</code></pre>

blocks|key|1465783|text|试一试|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1465784|MyTable.EmptyDataSet;|code-block|syntax|javascript|1465785|可能还有更多的工作要做，但您一开始并没有说明如何填充MyTable。|offset|length|style|CODE|1465786|entityMap^0|0|0|Q|7|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Try

<pre><code>MyTable.EmptyDataSet;
</code></pre>

There may be a bit more to do than that, but you don't say how you are populating <code>MyTable</code> in the first place.

blocks|key|1465731|text|试一试|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1465732|如果对所有行执行删除操作，则会影响性能。|1465733|如果这不起作用，那么为什么不创建dataset运行时，然后释放对象。|1465734|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

Try

as doing delete for all the rows would hamper the performance.

If that does not work then why don you create the dataset runtime and then free the object.

blocks|key|1945155|text|我建议您对作业使用存储过程，而不是使用应用程序中的SQL。存储过程简单、快速，因为它们直接在服务器上运行。只需为您的表创建一个存储过程；|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1945156|sp_deleteall|blockquote|1945157|并在其中执行一行sql：|1945158|从mytable中删除|1945159|从您的应用程序中，在表单上放置一个TFDStoredProc，将其链接到服务器上的存储过程，然后调用该过程|1945160|sp_deleteall.ExecProc；|1945161|要知道删除了多少条记录，只需在过程执行之后调用：|1945162|ShowMessage(IntToStr(sp_deleteall.RowsAffected)+%2B+'+records+were+deleted.');|code-block|syntax|javascript|1945163|试试吧..。|1945164|entityMap^0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|X|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Y|8|@]|9|@]|A|$]]|$1|E|3|F|5|6|7|Z|8|@]|9|@]|A|$]]|$1|G|3|H|5|D|7|10|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|11|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|12|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|13|8|@]|9|@]|A|$]]|$1|O|3|P|5|Q|7|14|8|@]|9|@]|A|$R|S]]|$1|T|3|U|5|6|7|15|8|@]|9|@]|A|$]]|$1|V|3|-4|5|6|7|16|8|@]|9|@]|A|$]]]|W|$]]

I would suggest you use a stored procedure for the job and not SQL from your application. Stored procedures are simple to make and blazing fast because they operate directly on the server.
Just create a stored procedure for your table; 

<blockquote>
 sp_deleteall
</blockquote>

and do in it a single line of sql: 

<blockquote>
 delete from mytable
</blockquote>

From your application,drop a TFDStoredProc on the form, link it to your stored procedure on the server and just call on the procedure
`

<blockquote>
 sp_deleteall.ExecProc;
</blockquote>

To know how many records were deleted just call, after the procedure execution :

<pre><code>ShowMessage(IntToStr(sp_deleteall.RowsAffected) + ' records were deleted.');
</code></pre>

Try it ...

blocks|key|1945182|text|从最快到最慢。前两个命令是您执行服务器端的命令。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1945183|关闭表并执行SQL命令TRUNCATE+TABLENAME;，然后重新打开。这需要对表的独占访问。|ordered-list-item|offset|length|style|CODE|1945184|使用SQL命令DELETE+FROM+TABLENAME;。这不需要独占访问。|1945185|使用循环客户端。速度要慢得多，并触发了许多事件客户端。|1945186|entityMap^0|0|B|J|0|7|M|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@$E|Q|F|R|G|H]]|9|@]|A|$]]|$1|I|3|J|5|D|7|S|8|@$E|T|F|U|G|H]]|9|@]|A|$]]|$1|K|3|L|5|D|7|V|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|N|$]]

Form fastest to slowest. First two are commands you execute server side.

<ol>
<li>Close the table and do a SQL DDL command <code>TRUNCATE TABLENAME;</code> and then reopen. This requires exclusive access to the table.</li>
<li>Use a SQL DML command <code>DELETE FROM TABLENAME;</code>. This does not require exclusive access.</li>
<li>Use a loop client side. A lot slower and triggers a lot of events client side. </li>
</ol>

blocks|key|1465830|text|要删除FDMemTable上的所有记录，您所需要做的就是|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1465831|MyTable.Active+:=+False;|code-block|syntax|javascript|1465832|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

all you need to do for delete all records on a FDMemTable is

<pre><code>MyTable.Active := False;
</code></pre>

Iam trying to delete all records in my FDTable component using , 

<code>mytable.Delete;</code>

but no record is getting deleted.

can any one suggest me a way to delete all records in a FdTable.

EDIT

i modified it in this way,

<pre><code> for i := mytable.RecordCount - 1 downto 0 do
 begin
 mytable.Delete;
 end;
 mytable.Refresh;
</code></pre>

but it is taking lot of time because there a lot rows in my fdtable.

Delphi Delete all records from FDTable

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我试图删除我的FDTable组件中的所有记录，mytable.Delete;但没有记录被删除。有人能建议我删除FdTable中的所有记录吗？编辑我用这种方式修改了它，  for i := mytable.RecordCount - 1 downto 0 do  begin    mytable.Delete;  end;  mytable.Refresh;但这需要很长时间，因为我的可操作表中有很多

问Delphi从FDTable删除所有记录
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