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我正在尝试使用Aerospike 批量加载程序从制表符分隔文件中为集群播种数据。

源数据如下所示：

set key segments
segment 123 10,20,30,40,50
segment 234 40,50,60,70

第三列“segments”包含一个逗号分隔的整数列表。

我创建了一个 JSON 模板：

{
  "version" : "1.0",
  "input_type" : "csv",
  "csv_style": { "delimiter": " " , "n_columns_datafile": 3, "ignore_first_line": true}

  "key": {"column_name":"key", "type": "integer"},

  "set": { "column_name":"set" , "type": "string"},

  "binlist": [
    {"name": "segments",
      "value": {"column_name": "segments", "type": "list"}
    }
  ]
}

...并运行装载机：

java -cp aerospike-load-1.1-jar-with-dependencies.jar com.aerospike.load.AerospikeLoad -c template.json data.tsv

当我查询 aql 中的记录时，它们似乎是一个字符串列表：

aql> select * from test
+--------------------------------+
| segments                       |
+--------------------------------+
| ["10", "20", "30", "40", "50"] |
| ["40", "50", "60", "70"]       |
+--------------------------------+

我要存储的数据是整数列表。是否有一种简单的方法可以将存储在此 bin 中的对象转换为整数列表（可能是 Lua UDF），或者可以对批量加载程序模板进行调整？

更新：

我试图通过创建一个 Lua UDF 将列表从字符串转换为整数来解决这个问题：

function convert_segment_list_to_integers(rec)
    for i=1, table.maxn(rec['segments']) do
        rec['segments'][i] = math.floor(tonumber(rec['segments'][i]))
    end
    aerospike:update(rec)
end

...注册它：

aql> register module 'convert_segment_list_to_integers.lua'

...然后尝试对我的集合执行：

aql> execute convert_segment_list_to_integers.convert_segment_list_to_integers() on test.segment

我启用了一些更详细的日志记录，并注意到 UDF 正在引发错误。显然，它期待 atable并且它通过了userdata：

Dec 04 2015 23:23:34 GMT: DEBUG (udf): (udf_rw.c:send_result:527) FAILURE when calling convert_segment_list_to_integers convert_segment_list_to_integers ...rospike/usr/udf/lua/convert_segment_list_to_integers.lua:2: bad argument #1 to 'maxn' (table expected, got userdata)
Dec 04 2015 23:23:34 GMT: DEBUG (udf): (udf_rw.c:send_udf_failure:407) Non-special LDT or General UDF Error(...rospike/usr/udf/lua/convert_segment_list_to_integers.lua:2: bad argument #1 to 'maxn' (table expected, got userdata))

似乎这maxn不是一个适用于userdata对象的方法。

你能看出需要做什么来解决这个问题吗？

4

1 回答 1

2

To convert your lists with string values to lists of integer values you can run the following record udf:

function convert_segment_list_to_integers(rec)
        local list_with_ints = list()
        for value in list.iterator(rec['segments']) do
                local int_value = math.floor(tonumber(value))
                list.append(list_with_ints, int_value)
        end
        rec['segments'] = list_with_ints
        aerospike:update(rec)
end

When you edit your existing lua module, make sure to re-run register module 'convert_segment_list_to_integers.lua'.

The cause of this issue is within the aerospike-loader tool: it will always assume/enforce strings as you can see in the following java code:

case LIST:
    /*
     * Assumptions
     * 1. Items are separated by a colon ','
     * 2. Item value will be a string
     * 3. List will be in double quotes
     * 
     * No support for nested maps or nested lists
     * 
     */
    List<String> list = new ArrayList<String>();
    String[] listValues = binRawText.split(Constants.LIST_DELEMITER, -1);
    if (listValues.length > 0) {
        for (String value : listValues) {
            list.add(value.trim());
        }
        bin = Bin.asList(binColumn.getBinNameHeader(), list);
    } else {
        bin = null;
        log.error("Error: Cannot parse to a list: " + binRawText);
    }
    break;

Source on Github: http://git.io/vRAQW

If you prefer, you can modify this code and re-compile to always assume integer list values. Change line 266 and 270 to something like this (untested):

List<Integer> list = new ArrayList<Integer>(); 
list.add(Integer.parseInt(value.trim());
于 2015-12-09T23:23:02.433 回答