Bulk Insert is a very important tool for any SSIS developer and is used by nearly every developer to load the Flat file into the staging table. Here we aren't going to describe Bulk Copy in full detail, but will discuss some common factors when using Bulk Copy.

Common Factors

Some of the common factors that we faced with BULK COPY are:

1.    When the Import Table has the Identity Columns

2.    When we do not want to Insert some records in a specified columns of a Table

3.    When data type mismatch occurs

4.    When Truncation Error occurs

Sometimes in the ETL process the flat file size is so heavy that we are unable to open it.

How to Solve This Problem

This type and many other types of problem with BULK COPY can be solved by using Format File. So here in this article we are going to describe the BULK COPY using format file.

Format file is a Metadata of table where we are importing the data from flat file. There are two types of format files: one is in text format and the other is in xml format. Generally, I prefer the xml format, but it just depends on the developer—there are no hard and fast rules.

Demonstration

Step 1 — The Flat File Format

Step 2 — The Destination Table

IF OBJECT_ID(N'[dbo].[tbl_StudentDetails]', N'U')IS NOT NULL
   DROP TABLE [dbo].[tbl_StudentDetails];
GO
CREATE TABLE [dbo].[tbl_StudentDetails]
    (
        StdRoll   INT         NOT NULL PRIMARY KEY,
        Stdname   VARCHAR(50) NULL,
        StdClass  INT         NULL,
        Section   CHAR(1)     NULL
      );
GO

Step 3 — Creating the Format File

The XML Format File

bcp PracticeDB.dbo.tbl_StudentDetails
format nul -c -f
E:\Preparation\SSIS\BCP\FmtStudentDetails.xml
-x -S JOYDEEP-LAPTOP\JOYDEEPSQL12 -T -q -t;

Here the XML format file name is FmtStudentDetails.xml and the Instance of the SQL Server name is JOYDEEP-LAPTOP\JOYDEEPSQL12.

 <?xml version="1.0" ?>
- <BCPFORMAT xmlns="http://schemas.microsoft.com/sqlserver/2004/bulkload/format"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
- <RECORD>
  <FIELD ID="1" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="12" />
  <FIELD ID="2" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="50"
COLLATION="SQL_Latin1_General_CP1_CI_AS" />
  <FIELD ID="3" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="12" />
  <FIELD ID="4" xsi:type="CharTerm" TERMINATOR="\r\n" MAX_LENGTH="1"
COLLATION="SQL_Latin1_General_CP1_CI_AS" />
  </RECORD>
- <ROW>
  <COLUMN SOURCE="1" NAME="StdRoll" xsi:type="SQLINT" />
  <COLUMN SOURCE="2" NAME="Stdname" xsi:type="SQLVARYCHAR" />
  <COLUMN SOURCE="3" NAME="StdClass" xsi:type="SQLINT" />
  <COLUMN SOURCE="4" NAME="Section" xsi:type="SQLCHAR" />
  </ROW>
  </BCPFORMAT>

The TEXT Format File

bcp PracticeDB.dbo.tbl_StudentDetails
format nul -c -f E:\Preparation\SSIS\BCP\FmtStudentDetails.fmt 
-S JOYDEEP-LAPTOP\JOYDEEPSQL12 -T -q -t;

10.0
4
1       SQLCHAR             0       12      ";"      1     StdRoll              ""
2       SQLCHAR             0       50      ";"      2     Stdname              
SQL_Latin1_General_CP1_CI_AS
3       SQLCHAR             0       12      ";"      3     StdClass             ""
4       SQLCHAR             0       10      "\r\n"   4     Section              
SQL_Latin1_General_CP1_CI_AS

If we want we can edit both the files. Suppose the StdRoll is an IDENTITY column and we do not want to insert records in the table for that, then we have to just edit it.

  <?xml version="1.0" ?>
- <BCPFORMAT xmlns="http://schemas.microsoft.com/sqlserver/2004/bulkload/format"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
- <RECORD>
  <FIELD ID="0" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="12" />
  <FIELD ID="2" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="50"
COLLATION="SQL_Latin1_General_CP1_CI_AS" />
  <FIELD ID="3" xsi:type="CharTerm" TERMINATOR=";" MAX_LENGTH="12" />
  <FIELD ID="4" xsi:type="CharTerm" TERMINATOR="\r\n" MAX_LENGTH="1"
COLLATION="SQL_Latin1_General_CP1_CI_AS" />
  </RECORD>
- <ROW>
  <COLUMN SOURCE="0" NAME="StdRoll" xsi:type="SQLINT" />
  <COLUMN SOURCE="2" NAME="Stdname" xsi:type="SQLVARYCHAR" />
  <COLUMN SOURCE="3" NAME="StdClass" xsi:type="SQLINT" />
  <COLUMN SOURCE="4" NAME="Section" xsi:type="SQLCHAR" />
  </ROW>
  </BCPFORMAT>

10.0
4
1       SQLCHAR             0       12      ";"      0     StdRoll              ""
2       SQLCHAR             0       50      ";"      2     Stdname              
SQL_Latin1_General_CP1_CI_AS
3       SQLCHAR             0       12      ";"      3     StdClass             ""
4       SQLCHAR             0       10      "\r\n"   4     Section              
SQL_Latin1_General_CP1_CI_AS

Here is an image of the code with highlighted lines, for you to better understand:

Step 4 — Using Format File for Bulk Insert 

BULK INSERT tbl_StudentDetails
   FROM 'E:\Preparation\SSIS\BCP\test.txt'
   WITH (FORMATFILE = 'E:\Preparation\SSIS\BCP\FmtStudentDetails.xml',
         FIELDTERMINATOR = ';',
             ROWTERMINATOR = '0x0A'
         );

BULK INSERT tbl_StudentDetails
   FROM 'E:\Preparation\SSIS\BCP\test.txt'
   WITH (FORMATFILE = 'E:\Preparation\SSIS\BCP\FmtStudentDetails.fmt,
         FIELDTERMINATOR = ';',
             ROWTERMINATOR = '0x0A'
         );

And, another image showing the highlighted lines:

Please note that the Format file is your Metadata of the table, so if the format file is generated properly the BULK INSERT is done successfully. We can Edit the format file according to our needs and by controlling the BULK INSERT.

Hope this helps!