使用psql复制csv时包含NULL值

Question

I have a csv with various data formats that I am trying to copy in to postgres. I am encountering this error every time because at line 97789 I have a few columns with empty cells.

Rather than deleting this row (and other rows that may contain NULL values), I'd like to find a solution to including them in the database. Column ma effective date is supposed to take an integer value. But when I try to use the following code - it doesn't work, probably because I am trying to input NULL as a string:

oakland=# \copy test_import FROM '/Users/Downloads/IE670_test.csv' DELIMITER ','  NULL AS 'NULL' csv
ERROR:  invalid input syntax for integer: "        "
CONTEXT:  COPY test_import, line 97789, column ma effective date (ccyymmdd): "        "

however, switching to NULL as NULL also doesn't work and produces a syntax error in psql . Is there an effective solution to including NULL values regardless of the data type in the column?

Here is the offending line in raw format:

048A706200600,48A-7062-6     ,17,3,5815,PRESLEY WAY                                       ,          ,OAKLAND                       ,94618,    ," $102,150.00 "," $38,259.00 ", $-   , $-   , $-   , $-   , $-   ," $7,000.00 ", $-   ," $133,409.00 ",2015,139807,20150527,20150901, ,                    ,                                                  ,                                                            ,          ,                              ,     ,    ,  , ,        , ,1100,Single family residential homes used as such

Answer 1

If the null-valued cells are truly empty, omit the NULL AS 'NULL' clause. Otherwise (as appears to be the case), replace the 'NULL' string with a string containing whatever is in those cells. You may need to ensure that the null values in the csv are consistent.

test.csv (one-space null):

1, ,3

SQL

create table csv (one int, two int, three int);

One space as null:

\copy csv from '~/test.csv' delimiter ',' null as ' ' csv;
COPY 1

Two spaces as null:

\copy csv from '~/test.csv' delimiter ',' null as '  ' csv;
ERROR:  invalid input syntax for integer: " "
CONTEXT:  COPY csv, line 1, column two: " "