MongoDB 自定义 Power BI DirectQuery 连接器问题 - 无法将 Bigint 转换为整数答案

【问题标题】：MongoDB Custom Power BI DirectQuery Connector Issue - Failed to Convert Bigint to IntegerMongoDB 自定义 Power BI DirectQuery 连接器问题 - 无法将 Bigint 转换为整数
【发布时间】：2019-09-04 22:43:18
【问题描述】：

我正在设置从本地 MongoDB 环境到 Microsoft Power BI 的 DirectQuery 连接。我使用来自 Microsoft (https://github.com/microsoft/DataConnectors/tree/master/samples) 的示例 ODBC 连接器创建了一个自定义连接器。我正在为 BI 连接器使用最新的 MongoDB ODBC 驱动程序和 MongoDB ODBC 驱动程序。我创建了一个系统数据源，用作我的自定义连接器的输入。

我将以下集合引入 Power BI for DirectQuery： tbllink 交通数据。我尝试使用 LastUpdate 字段创建切片器。当我过滤一个 LinkID（这是一个字段）时，我收到以下错误。

"ErrorMessage":"Failed to convert type bigint to integer, expression `LinkID` to 1506780."

"ErrorMessage":"This ODBC driver doesn't support SQL_FN_CVT_CONVERT or SQL_FN_CVT_CAST. You can override this by using SqlGetInfo for SQL_CONVERT_FUNCTIONS."

我似乎看到了转换错误，但我不确定如何解决连接器中的问题。

这是我的 SqlGetInfo 函数：

    SQLGetInfo = [
        // place custom overrides here
        SQL_SQL92_PREDICATES = ODBC[SQL_SP][All],
        SQL_AGGREGATE_FUNCTIONS = ODBC[SQL_AF][All],
        SQL_CONVERT_FUNCTIONS = ODBC[SQL_CVT][BIGINT]
    ],

//this is from OdbcConstants file that is called in Power Query file
SQL_CVT = [
BIGINT = 0x00004000
]

这里有更多 Power BI 跟踪日志：

    SqlTranslator/SqlParser/Parse {"Start":"2019-09-

03T19:55:54.6245555Z","Action":"SqlTranslator/SqlParser/Parse","HostProcessId":"12228","SQL":"\nSELECT MAX([t29].[LastUpdate])\n AS [a0],MIN([t29].[LastUpdate])\n AS [a1]\nFROM \n(\n(SELECT * FROM [tbllinktrafficdata (2)])\n)\n AS [t29]\nWHERE \n(\n[t29].[LinkID] = 1506780\n)\n ","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.1356012"}
SqlExpressionTranslator/Translate {"Start":"2019-09-03T19:55:54.7606768Z","Action":"SqlExpressionTranslator/Translate","HostProcessId":"12228","IsRecognized":"True","Result":"(environment) => Table.RenameColumns(let\r\n    t1133 = Table.RenameColumns(Table.PrefixColumns(environment[#\"tbllinktrafficdata (2)\"], \"tbllinktrafficdata (2)\"), {{\"tbllinktrafficdata (2)._id\", \"t29._id\"}, {\"tbllinktrafficdata (2).AgencyID\", \"t29.AgencyID\"}, {\"tbllinktrafficdata (2).DataType\", \"t29.DataType\"}, {\"tbllinktrafficdata (2).LastUpdate\", \"t29.LastUpdate\"}, {\"tbllinktrafficdata (2).LinkID\", \"t29.LinkID\"}, {\"tbllinktrafficdata (2).Occupancy\", \"t29.Occupancy\"}, {\"tbllinktrafficdata (2).Speed\", \"t29.Speed\"}, {\"tbllinktrafficdata (2).TravelTime\", \"t29.TravelTime\"}, {\"tbllinktrafficdata (2).Volume\", \"t29.Volume\"}}),\r\n    t1135 = Table.SelectRows(t1133, (t1134) => Value.NullableEquals(t1134[t29.LinkID], 1506780)),\r\n    t1140 = Table.Group(t1135, {}, {{\"a0\", (t1136) => List.Max(t1136[t29.LastUpdate])}, {\"a1\", (t1137) => List.Min(t1137[t29.LastUpdate])}}),\r\n    t1141 = Table.SelectColumns(t1140, {\"a0\", \"a1\"})\r\nin\r\n    t1141, {{\"a0\", \"a0\"}, {\"a1\", \"a1\"}})","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.1279102"}
SimpleDocumentEvaluator/GetResult/Evaluate {"Start":"2019-09-03T19:55:54.6208186Z","Action":"SimpleDocumentEvaluator/GetResult/Evaluate","HostProcessId":"12228","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.2835266"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9495926Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","Function Name":"VisitInvocation","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0000162"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9498087Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","Function Name":"VisitValueEqualsShared","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0000058"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9498281Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","ErrorMessage":"Failed to convert type bigint to integer, expression `LinkID` to 1506780.","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0057948"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9498205Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","Function Name":"AdjustForCompatibility","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0000034"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9556351Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","Function Name":"AdjustNumberValuesToPreventOverflow","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0000045"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9556433Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","Function Name":"SoftConvertSeries","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0000034"}
OdbcQuery/FoldingWarning {"Start":"2019-09-03T19:55:54.9556496Z","Action":"OdbcQuery/FoldingWarning","HostProcessId":"12228","ErrorMessage":"This ODBC driver doesn't support SQL_FN_CVT_CONVERT or SQL_FN_CVT_CAST. You can override this by using SqlGetInfo for SQL_CONVERT_FUNCTIONS.","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0002851"}
OdbcQueryDomain/ReportFoldingFailure {"Start":"2019-09-03T19:55:54.9566845Z","Action":"OdbcQueryDomain/ReportFoldingFailure","HostProcessId":"12228","Exception":"Exception:\r\nExceptionType: Microsoft.Mashup.Engine1.Runtime.FoldingFailureException, Microsoft.MashupEngine, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35\r\nMessage: Folding failed. Please take a look the information in the trace.\r\nStackTrace:\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.CallConvertOrCast(SqlExpression from, OdbcTypeMap toType)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.TryVisitConvert(OdbcTypeInfo fromType, OdbcTypeInfo toType, SqlExpression expression, SqlExpression& convertedExpression)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.TryConvert(OdbcTypeInfo typeInfo, OdbcScalarExpression expression, OdbcScalarExpression& convertedExpression)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.<SoftConvertSeries>d__191.MoveNext()\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.AdjustNumberValuesToPreventOverflow(OdbcScalarExpression left, OdbcScalarExpression right, Precision precision)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.AdjustNumberValuesForCompatibility(OdbcScalarExpression left, OdbcScalarExpression right, Precision precision)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.AdjustForCompatibility(OdbcScalarExpression left, OdbcScalarExpression right, Precision precision)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.VisitEquals(OdbcSqlExpression leftExpression, OdbcSqlExpression rightExpression, Precision precision, Boolean nullable)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.VisitValueEqualsShared(InvocationQueryExpression expression, Boolean nullable)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQueryExpressionVisitor.VisitInvocation(InvocationQueryExpression expression)\r\n   at Microsoft.Mashup.Engine1.Library.Odbc.OdbcQuery.SelectRows(FunctionValue function)\r\n\r\n\r\n","ProductVersion":"2.72.5556.801 (19.08)","ActivityId":"3ef90ded-79fc-4726-83bb-c98d8ccf5be7","Process":"Microsoft.Mashup.Container.NetFX45","Pid":22304,"Tid":1,"Duration":"00:00:00.0036644"}

【问题讨论】：

标签： mongodb powerbi powerquery connector

【解决方案1】：

我能够通过在 SqlColumn 函数中进行转换来进行转换。 Odbc SQL 类型取自 ODBC 常量 SQL_TYPE（包括在下面）

SQLColumns = (catalogName, schemaName, tableName, columnName, source) =>
                let
                    OdbcSqlType.BIG_INT = -5,
                    OdbcSqlType.INTEGER = 4,

                    FixDataType = (dataType) =>
                        if dataType = OdbcSqlType.BIG_INT then
                            OdbcSqlType.INTEGER
                        else
                            dataType,
                    Transform = Table.TransformColumns(source, { { "DATA_TYPE", FixDataType } })
                in
                    // the if statement conditions will force the values to evaluated/written to diagnostics
                    if (Diagnostics.LogValue("SQLColumns.TableName", tableName) <> "***" and Diagnostics.LogValue("SQLColumns.ColumnName", columnName) <> "***") then
                        let
                            // Outputting the entire table might be too large, and result in the value being truncated.
                            // We can output a row at a time instead with Table.TransformRows()
                            rows = Table.TransformRows(Transform, each Diagnostics.LogValue("SQLColumns", _)),
                            toTable = Table.FromRecords(rows)
                        in
                            Value.ReplaceType(toTable, Value.Type(Transform))
                    else
                        Transform,

SQL 数据类型

SQL_TYPE =
    [
        // Base data types (sql.h)
        UNKNOWN             = 0,
        NULL                = 0,
        CHAR                = 1,
        NUMERIC             = 2,
        DECIMAL             = 3,
        INTEGER             = 4,
        SMALLINT            = 5,
        FLOAT               = 6,
        REAL                = 7,
        DOUBLE              = 8,
        DATETIME            = 9,      // V3 Only
        VARCHAR             = 12,

        // Unicode types (sqlucode.h)
        WCHAR               = -8,
        WVARCHAR            = -9,
        WLONGVARCHAR        = -10,

        // Extended data types (sqlext.h)
        INTERVAL            = 10,    // V3 Only
        TIME                = 10,
        TIMESTAMP           = 11,
        LONGVARCHAR         = -1,
        BINARY              = -2,
        VARBINARY           = -3,
        LONGVARBINARY       = -4,
        BIGINT              = -5,
        TINYINT             = -6,
        BIT                 = -7,
        GUID                = -11,   // V3 Only

        // One-parameter shortcuts for date/time data types.
        TYPE_DATE           = 91,
        TYPE_TIME           = 92,
        TYPE_TIMESTAMP      = 93,

        // SQL Server Types -150 to -159 (sqlncli.h)
        SS_VARIANT          = -150,
        SS_UDT              = -151,
        SS_XML              = -152,
        SS_TABLE            = -153,
        SS_TIME2            = -154,
        SS_TIMESTAMPOFFSET  = -155
    ],

【讨论】：