Re: Cannot dump/restore text value \N - Mailing list pgsql-hackers
| From | Manfred Koizar |
|---|---|
| Subject | Re: Cannot dump/restore text value \N |
| Date | |
| Msg-id | 6tl7ovsbavt91htnmnnec0gtfu0979r77r@email.aon.at Whole thread Raw |
| In response to | Re: Cannot dump/restore text value \N (Tom Lane <tgl@sss.pgh.pa.us>) |
| Responses |
Re: Cannot dump/restore text value \N
|
| List | pgsql-hackers |
On Sun, 05 Oct 2003 19:12:50 -0400, Tom Lane <tgl@sss.pgh.pa.us>
wrote:
>it seems we have to compare the null representation string to the
>pre-debackslashing input.
Here is a patch that does this and adds a few regression tests.
>(This is probably fairly easy to make happen
>in CVS tip, but it might be pretty painful in 7.3.)
There haven't been too much changes in this area between 7.3 and 7.4.
A patch against 7.3.4 will follow ...
Servus
Manfred
diff -ruN ../base/src/backend/commands/copy.c src/backend/commands/copy.c
--- ../base/src/backend/commands/copy.c 2003-08-28 15:52:34.000000000 +0200
+++ src/backend/commands/copy.c 2003-10-08 10:43:02.000000000 +0200
@@ -90,7 +90,8 @@
char *delim, char *null_print);
static void CopyFrom(Relation rel, List *attnumlist, bool binary, bool oids,
char *delim, char *null_print);
-static char *CopyReadAttribute(const char *delim, CopyReadResult *result);
+static char *CopyReadAttribute(const char *delim, const char *nullst,
+ CopyReadResult *result, bool *isnull);
static Datum CopyReadBinaryAttribute(int column_no, FmgrInfo *flinfo,
Oid typelem, bool *isnull);
static void CopyAttributeOut(char *string, char *delim);
@@ -1361,7 +1362,7 @@
if (file_has_oids)
{
- string = CopyReadAttribute(delim, &result);
+ string = CopyReadAttribute(delim, null_print, &result, &isnull);
if (result == END_OF_FILE && *string == '\0')
{
@@ -1370,7 +1371,7 @@
break;
}
- if (strcmp(string, null_print) == 0)
+ if (isnull)
ereport(ERROR,
(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
errmsg("null OID in COPY data")));
@@ -1403,7 +1404,7 @@
errmsg("missing data for column \"%s\"",
NameStr(attr[m]->attname))));
- string = CopyReadAttribute(delim, &result);
+ string = CopyReadAttribute(delim, null_print, &result, &isnull);
if (result == END_OF_FILE && *string == '\0' &&
cur == attnumlist && !file_has_oids)
@@ -1413,7 +1414,7 @@
break; /* out of per-attr loop */
}
- if (strcmp(string, null_print) == 0)
+ if (isnull)
{
/* we read an SQL NULL, no need to do anything */
}
@@ -1442,7 +1443,7 @@
{
if (attnumlist == NIL && !file_has_oids)
{
- string = CopyReadAttribute(delim, &result);
+ string = CopyReadAttribute(delim, null_print, &result, &isnull);
if (result == NORMAL_ATTR || *string != '\0')
ereport(ERROR,
(errcode(ERRCODE_BAD_COPY_FILE_FORMAT),
@@ -1650,14 +1651,13 @@
* END_OF_FILE: EOF indicator
* In all cases, the string read up to the terminator is returned.
*
- * Note: This function does not care about SQL NULL values -- it
- * is the caller's responsibility to check if the returned string
- * matches what the user specified for the SQL NULL value.
- *
* delim is the column delimiter string.
+ * nullst says how NULL values are represented.
+ * *isnull is set true if a null attribute, else false.
*/
static char *
-CopyReadAttribute(const char *delim, CopyReadResult *result)
+CopyReadAttribute(const char *delim, const char *nullst,
+ CopyReadResult *result, bool *isnull)
{
int c;
int delimc = (unsigned char) delim[0];
@@ -1665,6 +1665,17 @@
unsigned char s[2];
char *cvt;
int j;
+ bool matchnull = true;
+ int matchlen = 0;
+
+#define CHECK_MATCH(c) \
+ do { \
+ if (matchnull) \
+ if (c == nullst[matchlen]) \
+ ++matchlen; \
+ else \
+ matchnull = false; \
+ } while (0)
s[1] = 0;
@@ -1733,6 +1744,7 @@
}
if (c == delimc)
break;
+ CHECK_MATCH(c);
if (c == '\\')
{
c = CopyGetChar();
@@ -1741,6 +1753,7 @@
*result = END_OF_FILE;
goto copy_eof;
}
+ CHECK_MATCH(c);
switch (c)
{
case '0':
@@ -1760,11 +1773,13 @@
{
val = (val << 3) + OCTVALUE(c);
CopyDonePeek(c, true /* pick up */ );
+ CHECK_MATCH(c);
c = CopyPeekChar();
if (ISOCTAL(c))
{
val = (val << 3) + OCTVALUE(c);
CopyDonePeek(c, true /* pick up */ );
+ CHECK_MATCH(c);
}
else
{
@@ -1789,15 +1804,6 @@
}
break;
- /*
- * This is a special hack to parse `\N' as
- * <backslash-N> rather then just 'N' to provide
- * compatibility with the default NULL output. -- pe
- */
- case 'N':
- appendStringInfoCharMacro(&attribute_buf, '\\');
- c = 'N';
- break;
case 'b':
c = '\b';
break;
@@ -1871,6 +1877,7 @@
*result = END_OF_FILE;
goto copy_eof;
}
+ CHECK_MATCH(c);
appendStringInfoCharMacro(&attribute_buf, c);
}
}
@@ -1878,6 +1885,8 @@
copy_eof:
+ *isnull = (matchnull && (nullst[matchlen] == '\0'));
+
if (client_encoding != server_encoding)
{
cvt = (char *) pg_client_to_server((unsigned char *) attribute_buf.data,
diff -ruN ../base/src/test/regress/expected/copy2.out src/test/regress/expected/copy2.out
--- ../base/src/test/regress/expected/copy2.out 2003-07-27 06:53:11.000000000 +0200
+++ src/test/regress/expected/copy2.out 2003-10-07 21:12:16.000000000 +0200
@@ -2,7 +2,7 @@
a serial,
b int,
c text not null default 'stuff',
- d text not null,
+ d text,
e text
);
NOTICE: CREATE TABLE will create implicit sequence "x_a_seq" for SERIAL column "x.a"
@@ -48,23 +48,38 @@
CONTEXT: COPY FROM, line 1
-- various COPY options: delimiters, oids, NULL string
COPY x (b, c, d, e) from stdin with oids delimiter ',' null 'x';
+COPY x from stdin WITH DELIMITER AS ';' NULL AS '';
+COPY x from stdin WITH DELIMITER AS ':' NULL AS '\\X';
-- check results of copy in
SELECT * FROM x;
- a | b | c | d | e
--------+----+-------+--------+----------------------
- 10000 | 21 | 31 | 41 | before trigger fired
- 10001 | 22 | 32 | 42 | before trigger fired
- 10002 | 23 | 33 | 43 | before trigger fired
- 10003 | 24 | 34 | 44 | before trigger fired
- 10004 | 25 | 35 | 45 | before trigger fired
- 10005 | 26 | 36 | 46 | before trigger fired
- 6 | | 45 | 80 | before trigger fired
- 1 | 1 | stuff | test_1 | after trigger fired
- 2 | 2 | stuff | test_2 | after trigger fired
- 3 | 3 | stuff | test_3 | after trigger fired
- 4 | 4 | stuff | test_4 | after trigger fired
- 5 | 5 | stuff | test_5 | after trigger fired
-(12 rows)
+ a | b | c | d | e
+-------+----+------------+--------+----------------------
+ 9999 | | \N | NN | before trigger fired
+ 10000 | 21 | 31 | 41 | before trigger fired
+ 10001 | 22 | 32 | 42 | before trigger fired
+ 10002 | 23 | 33 | 43 | before trigger fired
+ 10003 | 24 | 34 | 44 | before trigger fired
+ 10004 | 25 | 35 | 45 | before trigger fired
+ 10005 | 26 | 36 | 46 | before trigger fired
+ 6 | | 45 | 80 | before trigger fired
+ 7 | | x | \x | before trigger fired
+ 8 | | , | \, | before trigger fired
+ 3000 | | c | | before trigger fired
+ 4000 | | C | | before trigger fired
+ 4001 | 1 | empty | | before trigger fired
+ 4002 | 2 | null | | before trigger fired
+ 4003 | 3 | Backslash | \ | before trigger fired
+ 4004 | 4 | BackslashX | \X | before trigger fired
+ 4005 | 5 | N | N | before trigger fired
+ 4006 | 6 | BackslashN | \N | before trigger fired
+ 4007 | 7 | XX | XX | before trigger fired
+ 4008 | 8 | Delimiter | : | before trigger fired
+ 1 | 1 | stuff | test_1 | after trigger fired
+ 2 | 2 | stuff | test_2 | after trigger fired
+ 3 | 3 | stuff | test_3 | after trigger fired
+ 4 | 4 | stuff | test_4 | after trigger fired
+ 5 | 5 | stuff | test_5 | after trigger fired
+(25 rows)
-- COPY w/ oids on a table w/o oids should fail
CREATE TABLE no_oids (
@@ -80,6 +95,7 @@
ERROR: table "no_oids" does not have OIDs
-- check copy out
COPY x TO stdout;
+9999 \N \\N NN before trigger fired
10000 21 31 41 before trigger fired
10001 22 32 42 before trigger fired
10002 23 33 43 before trigger fired
@@ -87,12 +103,25 @@
10004 25 35 45 before trigger fired
10005 26 36 46 before trigger fired
6 \N 45 80 before trigger fired
+7 \N x \\x before trigger fired
+8 \N , \\, before trigger fired
+3000 \N c \N before trigger fired
+4000 \N C \N before trigger fired
+4001 1 empty before trigger fired
+4002 2 null \N before trigger fired
+4003 3 Backslash \\ before trigger fired
+4004 4 BackslashX \\X before trigger fired
+4005 5 N N before trigger fired
+4006 6 BackslashN \\N before trigger fired
+4007 7 XX XX before trigger fired
+4008 8 Delimiter : before trigger fired
1 1 stuff test_1 after trigger fired
2 2 stuff test_2 after trigger fired
3 3 stuff test_3 after trigger fired
4 4 stuff test_4 after trigger fired
5 5 stuff test_5 after trigger fired
COPY x (c, e) TO stdout;
+\\N before trigger fired
31 before trigger fired
32 before trigger fired
33 before trigger fired
@@ -100,12 +129,25 @@
35 before trigger fired
36 before trigger fired
45 before trigger fired
+x before trigger fired
+, before trigger fired
+c before trigger fired
+C before trigger fired
+empty before trigger fired
+null before trigger fired
+Backslash before trigger fired
+BackslashX before trigger fired
+N before trigger fired
+BackslashN before trigger fired
+XX before trigger fired
+Delimiter before trigger fired
stuff after trigger fired
stuff after trigger fired
stuff after trigger fired
stuff after trigger fired
stuff after trigger fired
COPY x (b, e) TO stdout WITH NULL 'I''m null';
+I'm null before trigger fired
21 before trigger fired
22 before trigger fired
23 before trigger fired
@@ -113,6 +155,18 @@
25 before trigger fired
26 before trigger fired
I'm null before trigger fired
+I'm null before trigger fired
+I'm null before trigger fired
+I'm null before trigger fired
+I'm null before trigger fired
+1 before trigger fired
+2 before trigger fired
+3 before trigger fired
+4 before trigger fired
+5 before trigger fired
+6 before trigger fired
+7 before trigger fired
+8 before trigger fired
1 after trigger fired
2 after trigger fired
3 after trigger fired
diff -ruN ../base/src/test/regress/sql/copy2.sql src/test/regress/sql/copy2.sql
--- ../base/src/test/regress/sql/copy2.sql 2003-05-14 05:26:03.000000000 +0200
+++ src/test/regress/sql/copy2.sql 2003-10-07 20:49:49.000000000 +0200
@@ -2,7 +2,7 @@
a serial,
b int,
c text not null default 'stuff',
- d text not null,
+ d text,
e text
);
@@ -27,6 +27,7 @@
FOR EACH ROW EXECUTE PROCEDURE fn_x_before();
COPY x (a, b, c, d, e) from stdin;
+9999 \N \\N \NN \N
10000 21 31 41 51
\.
@@ -74,6 +75,24 @@
-- various COPY options: delimiters, oids, NULL string
COPY x (b, c, d, e) from stdin with oids delimiter ',' null 'x';
500000,x,45,80,90
+500001,x,\x,\\x,\\\x
+500002,x,\,,\\\,,\\
+\.
+
+COPY x from stdin WITH DELIMITER AS ';' NULL AS '';
+3000;;c;;
+\.
+
+COPY x from stdin WITH DELIMITER AS ':' NULL AS '\\X';
+4000:\X:C:\X:\X
+4001:1:empty::
+4002:2:null:\X:\X
+4003:3:Backslash:\\:\\
+4004:4:BackslashX:\\X:\\X
+4005:5:N:\N:\N
+4006:6:BackslashN:\\N:\\N
+4007:7:XX:\XX:\XX
+4008:8:Delimiter:\::\:
\.
-- check results of copy in
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