ConvertTo-Json不会将哈希表的数组转换为JSON

Question

我已经干了一个小时了，还是搞不清楚。下面的代码构建一个哈希表数组，将该数组与其他一组键值对一起添加到另一个哈希表中，然后将整个批次转换为JSON：

$01_ch_channel_hist_id = @{"ColumnName"="01_ch_channel_hist_id";"ColumnType"="bigint"}
$02_ch_channel_id = @{"ColumnName"="02_ch_channel_id";"ColumnType"="bigint"}
$08_ch_load_id = @{"ColumnName"="08_ch_load_id";"ColumnType"="bigint"}
$columns = $01_ch_channel_hist_id,$02_ch_channel_id,$08_ch_load_id
$ChannelDimH = @{}
$ChannelDimH.Add("Columns",$columns)
$ChannelDimH.Add("TableName","CHANNEL_DIM_H")
$ChannelDimH.Add("UniqueColumn","channel_id")
$tables = @()
$tables += $ChannelDimH
$sqoopOracleTableAndColumnMetadata = @{}
$sqoopOracleTableAndColumnMetadata.Add("tables",$tables)

$sqoopOracleTableAndColumnMetadata | ConvertTo-Json

下面是输出：

{
    "tables":  [
                   {
                       "TableName":  "CHANNEL_DIM_H",
                       "UniqueColumn":  "channel_id",
                       "Columns":  "System.Collections.Hashtable System.Collections.Hashtable System.Collections.Hashtable"
                   }
               ]
}

请注意，"Columns“数组中的hastables返回如下：

"System.Collections.Hashtable System.Collections.Hashtable System.Collections.Hashtable"

这些哈希表中的数据没有出现在我的JSON文档中。为什么不行？

Answer 1

我想通了。对ConvertTo-Json的调用需要深度指定

$01_ch_channel_hist_id = @{"ColumnName"="01_ch_channel_hist_id";"ColumnType"="bigint"}
$02_ch_channel_id = @{"ColumnName"="02_ch_channel_id";"ColumnType"="bigint"}
$08_ch_load_id = @{"ColumnName"="08_ch_load_id";"ColumnType"="bigint"}
$columns = $01_ch_channel_hist_id,$02_ch_channel_id,$08_ch_load_id
$ChannelDimH = @{}
$ChannelDimH.Add("Columns",$columns)
$ChannelDimH.Add("TableName","CHANNEL_DIM_H")
$ChannelDimH.Add("UniqueColumn","channel_id")
$tables = @()
$tables += $ChannelDimH
$sqoopOracleTableAndColumnMetadata = @{"tables"=$tables}
#$sqoopOracleTableAndColumnMetadata.Add("tables",$tables)

$sqoopOracleTableAndColumnMetadata | ConvertTo-Json -Depth 4