SQL won't insert null values with BULK INSERT

Question

I have a CSV file and each line looks similar to this:

EASTTEXAS,NULL,BELLVILLE AREA,NULL,BELLVILLE AREA,RGP,NULL,NULL,0,NULL,NULL,NULL,1,1,PM,PM Settings,NU         


        

Answer 1

According to:

http://msdn.microsoft.com/en-us/library/ms187887.aspx

null values can be inserted by having an empty field within your file.

Example file was:

1,,DataField3
2,,DataField3

Example method of importing file keeping nulls is:

USE AdventureWorks;
GO
BULK INSERT MyTestDefaultCol2
FROM 'C:\MyTestEmptyField2-c.Dat'
WITH (
    DATAFILETYPE = 'char',
    FIELDTERMINATOR = ',',
    KEEPNULLS
);
GO

Granted, this means you'll have to change your "NULL"s to "", and any empty strings you did want as empty string would be interpreted as nulls, but it might be enough to get you started? I would imagine to keep your empty string columns they would need to be changed from

field1,,field2

to

field1,"",field2

as example

Answer 2

A late PS.

Note that there seems to be a bug if the last column is a DATETIME type and the value is null, then you MUST have a (normally superfluous but accepted) field separator after the empty field, before the line-separator, or you'll get an error.

ADD: This does not consistently work (sometimes it does though!?!?), to make it stable change your ROWterminator to begin with the FIELDterminator

e.g. FIELDTERMINATOR = '#', ROWTERMINATOR = '#\n'

Below an example of the error you get when it messes things up:

Bulk load data conversion error (type mismatch or invalid character for the specified codepage) for row 1, column 31 (MyDateTimeField).

(And yes I tried an all ASCII example with less than 7F chars and got the same)

Example:

The first bulks fails a lot. The other fails on the fifth only, despite the similarity with the second, but nothing is allowed at the end in this special case...

Test data:

1#2017-06-13 19:00:11.247#0##2017-06-13 19:00:11.247#
2#2017-06-13 19:09:08.817#0##2017-06-13 19:00:11.247#123#
3#2017-06-13 18:44:07.980#1###
4#2017-06-13 09:39:18.367#11## #
5#2017-06-13 09:39:18.370#4###123#

and sql

CREATE TABLE TEST_Bulk(
    id int,
    ts1 datetime,
    txt varchar(40) NULL,
    ts2 datetime,
    ts3 datetime,
) 
GO

BULK INSERT TEST_Bulk FROM 'D:\File.txt' WITH (FIRSTROW=1, FIELDTERMINATOR = '#', ROWTERMINATOR = '\n', CODEPAGE= 'ACP' ,TABLOCK)

BULK INSERT TEST_Bulk FROM 'D:\File.txt' WITH (FIRSTROW=1, FIELDTERMINATOR = '#', ROWTERMINATOR = '#\n', CODEPAGE= 'ACP' ,TABLOCK)

select * from TEST_Bulk

drop table TEST_Bulk