Thread: Copy out wording
Our documentation for COPY (http://www.postgresql.org/docs/8.4/static/sql-copy.html) has the following to say: " The CSV format has no standard way to distinguish a NULL value from an empty string. PostgreSQL's COPY handles this by quoting. A NULL is output as the NULL string and is not quoted, while a data value matching the NULL string is quoted. Therefore, using the default settings, a NULL is written as an unquoted empty string, while an empty string is written with double quotes (""). Reading values follows similar rules. You can use FORCE NOT NULL to prevent NULL input comparisons for specific columns. " Shouldn't that be: "A NULL is output as the NULL string and is not quoted, while a data value matching the empty string is quoted"? If not, then what really is the difference between a NULL and a NULL string? -- Magnus Hagander Me: http://www.hagander.net/ Work: http://www.redpill-linpro.com/
> Shouldn't that be: > "A NULL is output as the NULL string and is not quoted, while a data > value matching the empty string is quoted"? sure, the document seems to has mistake. and i parse csv format with same way in import function ----------------------------------------------- Quan Zongliang quanzongliang@gmail.com