未验证 提交 bf2d3909 编写于 作者: S Shengliang Guan 提交者: GitHub

Merge pull request #3937 from songtianyi/master

fix: docs and tests typos, taos_fetch_subfields --> taos_fetch_fields…
......@@ -51,8 +51,8 @@ INTERVAL(1M)</code></pre>
<li><p>mseconds:查询数据库更新的时间间隔,单位为毫秒。一般设置为1000毫秒。返回值为指向TDengine_SUB 结构的指针,如果返回为空,表示失败。</p></li>
</ul><li><p><code>TAOS_ROW taos_consume(TAOS_SUB *tsub)</code>
</p><p>该函数用来获取订阅的结果,用户应用程序将其置于一个无限循环语句。如果数据库有新记录到达,该API将返回该最新的记录。如果没有新的记录,该API将阻塞。如果返回值为空,说明系统出错。参数说明:</p></li><ul><li><p>tsub:taos_subscribe的结构体指针。</p></li></ul><li><p><code>void taos_unsubscribe(TAOS_SUB *tsub)</code></p><p>取消订阅。应用程序退出时,务必调用该函数以避免资源泄露。</p></li>
<li><p><code>int taos_num_subfields(TAOS_SUB *tsub)</code></p><p>获取返回的一行记录中数据包含多少列。</p></li>
<li><p><code>TAOS_FIELD *taos_fetch_subfields(TAOS_SUB *tsub)</code></p><p>获取每列数据的属性(数据类型、名字、长度),与taos_num_subfileds配合使用,可解析返回的每行数据。</p></li></ul>
<li><p><code>int taos_num_fields(TAOS_SUB *tsub)</code></p><p>获取返回的一行记录中数据包含多少列。</p></li>
<li><p><code>TAOS_FIELD *taos_fetch_fields(TAOS_SUB *tsub)</code></p><p>获取每列数据的属性(数据类型、名字、长度),与taos_num_subfileds配合使用,可解析返回的每行数据。</p></li></ul>
<p>示例代码:请看安装包中的的示范程序</p>
<a class='anchor' id='缓存-(Cache)'></a><h2>缓存 (Cache)</h2>
<p>TDengine采用时间驱动缓存管理策略(First-In-First-Out,FIFO),又称为写驱动的缓存管理机制。这种策略有别于读驱动的数据缓存模式(Least-Recent-Use,LRU),直接将最近写入的数据保存在系统的缓存中。当缓存达到临界值的时候,将最早的数据批量写入磁盘。一般意义上来说,对于物联网数据的使用,用户最为关心最近产生的数据,即当前状态。TDengine充分利用了这一特性,将最近到达的(当前状态)数据保存在缓存中。</p>
......
......@@ -64,9 +64,9 @@
<p>该API用来获取最新消息,应用程序一般会将其置于一个无限循环语句中。其中参数tsub是taos_subscribe的返回值。如果数据库有新的记录,该API将返回,返回参数是一行记录。如果没有新的记录,该API将阻塞。如果返回值为空,说明系统出错,需要检查系统是否还在正常运行。</p></li>
<li><p><code>void taos_unsubscribe(TAOS_SUB *tsub)</code></p>
<p>该API用于取消订阅,参数tsub是taos_subscribe的返回值。应用程序退出时,需要调用该API,否则有资源泄露。</p></li>
<li><p><code>int taos_num_subfields(TAOS_SUB *tsub)</code></p>
<li><p><code>int taos_num_fields(TAOS_SUB *tsub)</code></p>
<p>该API用来获取返回的一排数据中数据的列数</p></li>
<li><p><code>TAOS_FIELD *taos_fetch_subfields(TAOS_RES *res)</code></p>
<li><p><code>TAOS_FIELD *taos_fetch_fields(TAOS_RES *res)</code></p>
<p>该API用来获取每列数据的属性(数据类型、名字、字节数),与taos_num_subfileds配合使用,可用来解析返回的一排数据。</p></li>
</ul>
<a class='anchor' id='Java-Connector'></a><h2>Java Connector</h2>
......@@ -259,4 +259,4 @@ conn.close()
_ "taosSql"
)</code></pre>
<p>taosSql驱动包内采用cgo模式,调用了TDengine的C/C++同步接口,与TDengine进行交互,因此,在数据库操作执行完成之前,客户端应用将处于阻塞状态。单个数据库连接,在同一时刻只能有一个线程调用API。客户应用可以建立多个连接,进行多线程的数据写入或查询处理。</p>
<p>更多使用的细节,请参考下载目录中的示例源码。</p><a href='../index.html'>回去</a></section></main></div><?php include($s.'/footer.php'); ?><script>$('pre').addClass('prettyprint linenums');PR.prettyPrint()</script><script src='lib/docs/liner.js'></script></body></html>
\ No newline at end of file
<p>更多使用的细节,请参考下载目录中的示例源码。</p><a href='../index.html'>回去</a></section></main></div><?php include($s.'/footer.php'); ?><script>$('pre').addClass('prettyprint linenums');PR.prettyPrint()</script><script src='lib/docs/liner.js'></script></body></html>
......@@ -72,9 +72,9 @@ The API is used to start a subscription session by given a handle. The parameter
The API used to get the new data from a TDengine server. It should be put in an infinite loop. The parameter <em>tsub</em> is the handle returned by <em>taos_subscribe</em>. If new data are updated, the API will return a row of the result. Otherwise, the API is blocked until new data arrives. If <em>NULL</em> pointer is returned, it means an error occurs.</p></li>
<li><p><code>void taos_unsubscribe(TAOS_SUB *tsub)</code>
Stop a subscription session by the handle returned by <em>taos_subscribe</em>.</p></li>
<li><p><code>int taos_num_subfields(TAOS_SUB *tsub)</code>
<li><p><code>int taos_num_fields(TAOS_SUB *tsub)</code>
The API used to get the number of fields in a row.</p></li>
<li><p><code>TAOS_FIELD *taos_fetch_subfields(TAOS_RES *res)</code>
<li><p><code>TAOS_FIELD *taos_fetch_fields(TAOS_RES *res)</code>
The API used to get the description of each column.</p></li>
</ul>
<a class='anchor' id='Java-Connector'></a><h2>Java Connector</h2>
......@@ -351,4 +351,4 @@ promise2.then(function(result) {
})</code></pre>
<h3>Example</h3>
<p>An example of using the NodeJS connector to create a table with weather data and create and execute queries can be found <a href="https://github.com/taosdata/TDengine/tree/master/tests/examples/nodejs/node-example.js">here</a> (The preferred method for using the connector)</p>
<p>An example of using the NodeJS connector to achieve the same things but without all the object wrappers that wrap around the data returned to achieve higher functionality can be found <a href="https://github.com/taosdata/TDengine/tree/master/tests/examples/nodejs/node-example-raw.js">here</a></p><a href='../index.html'>Back</a></section></main></div><?php include($s.'/footer.php'); ?><script>$('pre').addClass('prettyprint linenums');PR.prettyPrint()</script><script src='lib/docs/liner.js'></script></body></html>
\ No newline at end of file
<p>An example of using the NodeJS connector to achieve the same things but without all the object wrappers that wrap around the data returned to achieve higher functionality can be found <a href="https://github.com/taosdata/TDengine/tree/master/tests/examples/nodejs/node-example-raw.js">here</a></p><a href='../index.html'>Back</a></section></main></div><?php include($s.'/footer.php'); ?><script>$('pre').addClass('prettyprint linenums');PR.prettyPrint()</script><script src='lib/docs/liner.js'></script></body></html>
......@@ -308,12 +308,6 @@ extern "C" {
extern "C" {
pub fn taos_unsubscribe(tsub: *mut ::std::os::raw::c_void);
}
extern "C" {
pub fn taos_subfields_count(tsub: *mut ::std::os::raw::c_void) -> ::std::os::raw::c_int;
}
extern "C" {
pub fn taos_fetch_subfields(tsub: *mut ::std::os::raw::c_void) -> *mut TAOS_FIELD;
}
extern "C" {
pub fn taos_open_stream(
taos: *mut ::std::os::raw::c_void,
......
......@@ -37,16 +37,16 @@ impl Subscriber {
println!("subscribed to {} user:{}, db:{}, tb:{}, time:{}, mseconds:{}",
host, username, db, table, time, mseconds);
let mut fields = taos_fetch_subfields(tsub);
let mut fields = taos_fetch_fields(tsub);
if fields.is_null() {
taos_unsubscribe(tsub);
return Err("fetch subfields error")
return Err("fetch fields error")
}
let fcount = taos_subfields_count(tsub);
let fcount = taos_field_count(tsub);
if fcount == 0 {
taos_unsubscribe(tsub);
return Err("subfields count is 0")
return Err("fields count is 0")
}
Ok(Subscriber{tsub, fields, fcount})
......@@ -74,4 +74,4 @@ impl Drop for Subscriber {
fn drop(&mut self) {
unsafe {taos_unsubscribe(self.tsub);}
}
}
\ No newline at end of file
}
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册