Erlang 中的 Mysql

Question

我想通过 Erlang 在 Mysql 中获取数据，但我得到的数据输出显示所有 col_name 并且它不会一一呈现

这是我的输出:

{selected,["id","first_name","last_name"],
                              [{1,"Matt","Williamson"},
                               {2,"Matt","Williamson2"},
                               {3,"Matt","Williamson3"}]}}

我正在使用这段代码:

application:start(odbc),
ConnString = "DSN=mysqldb",
{ok, Conn} = odbc:connect(ConnString, []),
Results = odbc:sql_query(Conn, "SELECT * FROM test_table"),
io:format("~p",[Results]).

我怎么找不到{selected, [col_name]}？以及如何使用 Erlang 在 php 中像 for 循环一样逐一呈现数据？

它呈现

{1,"Matt","Williamson"}{2,"Matt","Williamson2"}{3,"Matt","Williamson3"} have

我希望它像这样呈现

1 have Matt Williamson
2 have Matt Williamson2
3 have Matt Williamson3

Answer 1

你可以像这样使用模式匹配:

{selected, _Column, Data} = odbc:sql_query(Conn, "SELECT * FROM test_table"),

然后使用 io:format("~p",[Data]).

你会得到:

[
 {1,"Matt","Williamson"},
 {2,"Matt","Williamson2"},
 {3,"Matt","Williamson3"}
]