Hi
I wrote a prototype of this patch, and it works well
postgres=# set client_encoding to 'latin2';
SET
Time: 1.488 ms
postgres=# \copy (select xmlelement(name xx, d) from d) to ~/d.xml (format
'raw')
COPY 1
Time: 1.108 ms
postgres=# copy (select xmlelement(name xx, d) from d) to stdout (format
'raw') ;
<?xml version="1.0" encoding="LATIN2"?><xx>příliš žluťoučký kůň</xx>Time:
1.000 ms
Regards
Pavel
2015-04-09 20:48 GMT+02:00 Pavel Stehule <pavel.steh...@gmail.com>:
> Hi
>
> This thread was finished without real work. I have a real use case -
> export XML doc in non utf8 encoding.
>
> http://www.postgresql.org/message-id/16174.1319228...@sss.pgh.pa.us
>
> I propose to implement new format option "RAW" like Tom proposed.
>
> It requires only one row, one column result - and result is just raw
> binary data without size.
>
> Objections? Ideas?
>
> Regards
>
> Pavel
>
commit 60c6701fe5a91c41e9ed0db99676c8b1a27e85e3
Author: Pavel Stehule <pavel.steh...@gooddata.com>
Date: Fri Apr 10 23:22:39 2015 +0200
initial
diff --git a/src/backend/commands/copy.c b/src/backend/commands/copy.c
index 92ff632..5701f8b 100644
--- a/src/backend/commands/copy.c
+++ b/src/backend/commands/copy.c
@@ -113,6 +113,7 @@ typedef struct CopyStateData
char *filename; /* filename, or NULL for STDIN/STDOUT */
bool is_program; /* is 'filename' a program to popen? */
bool binary; /* binary format? */
+ bool raw; /* raw format - data only */
bool oids; /* include OIDs? */
bool freeze; /* freeze rows on loading? */
bool csv_mode; /* Comma Separated Value format? */
@@ -348,6 +349,13 @@ SendCopyBegin(CopyState cstate)
int16 format = (cstate->binary ? 1 : 0);
int i;
+ if (cstate->binary)
+ format = 1;
+ else if (cstate->raw)
+ format = 2;
+ else
+ format = 0;
+
pq_beginmessage(&buf, 'H');
pq_sendbyte(&buf, format); /* overall format */
pq_sendint(&buf, natts, 2);
@@ -359,7 +367,7 @@ SendCopyBegin(CopyState cstate)
else if (PG_PROTOCOL_MAJOR(FrontendProtocol) >= 2)
{
/* old way */
- if (cstate->binary)
+ if (cstate->binary || cstate->raw)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("COPY BINARY is not supported to stdout or from stdin")));
@@ -371,7 +379,7 @@ SendCopyBegin(CopyState cstate)
else
{
/* very old way */
- if (cstate->binary)
+ if (cstate->binary || cstate->raw)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("COPY BINARY is not supported to stdout or from stdin")));
@@ -485,7 +493,7 @@ CopySendEndOfRow(CopyState cstate)
switch (cstate->copy_dest)
{
case COPY_FILE:
- if (!cstate->binary)
+ if (!(cstate->binary || cstate->raw))
{
/* Default line termination depends on platform */
#ifndef WIN32
@@ -543,7 +551,7 @@ CopySendEndOfRow(CopyState cstate)
break;
case COPY_NEW_FE:
/* The FE/BE protocol uses \n as newline for all platforms */
- if (!cstate->binary)
+ if (!(cstate->binary || cstate->raw))
CopySendChar(cstate, '\n');
/* Dump the accumulated row as one CopyData message */
@@ -1005,6 +1013,8 @@ ProcessCopyOptions(CopyState cstate,
cstate->csv_mode = true;
else if (strcmp(fmt, "binary") == 0)
cstate->binary = true;
+ else if (strcmp(fmt, "raw") == 0)
+ cstate->raw = true;
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
@@ -1808,6 +1818,10 @@ CopyTo(CopyState cstate)
num_phys_attrs = tupDesc->natts;
cstate->null_print_client = cstate->null_print; /* default */
+ /* don't allow more columns for raw format */
+ if (tupDesc->natts > 1)
+ elog(ERROR, "too much columns for RAW output");
+
/* We use fe_msgbuf as a per-row buffer regardless of copy_dest */
cstate->fe_msgbuf = makeStringInfo();
@@ -1819,7 +1833,7 @@ CopyTo(CopyState cstate)
Oid out_func_oid;
bool isvarlena;
- if (cstate->binary)
+ if ((cstate->binary || cstate->raw))
getTypeBinaryOutputInfo(attr[attnum - 1]->atttypid,
&out_func_oid,
&isvarlena);
@@ -1858,7 +1872,7 @@ CopyTo(CopyState cstate)
tmp = 0;
CopySendInt32(cstate, tmp);
}
- else
+ else if (!cstate->raw)
{
/*
* For non-binary copy, we need to convert null_print to file
@@ -1970,7 +1984,7 @@ CopyOneRowTo(CopyState cstate, Oid tupleOid, Datum *values, bool *nulls)
CopySendInt32(cstate, tupleOid);
}
}
- else
+ else if (!cstate->raw)
{
/* Text format has no per-tuple header, but send OID if wanted */
/* Assume digits don't need any quoting or encoding conversion */
@@ -1998,14 +2012,16 @@ CopyOneRowTo(CopyState cstate, Oid tupleOid, Datum *values, bool *nulls)
if (isnull)
{
- if (!cstate->binary)
+ if (cstate->raw)
+ elog(ERROR, "cannot to push NULL in raw output");
+ else if (!cstate->binary)
CopySendString(cstate, cstate->null_print_client);
else
CopySendInt32(cstate, -1);
}
else
{
- if (!cstate->binary)
+ if (!(cstate->binary || cstate->raw))
{
string = OutputFunctionCall(&out_functions[attnum - 1],
value);
diff --git a/src/interfaces/libpq/fe-protocol3.c b/src/interfaces/libpq/fe-protocol3.c
index a847f08..135c052 100644
--- a/src/interfaces/libpq/fe-protocol3.c
+++ b/src/interfaces/libpq/fe-protocol3.c
@@ -1352,6 +1352,8 @@ getCopyStart(PGconn *conn, ExecStatusType copytype)
*/
format = (int) ((int16) format);
result->attDescs[i].format = format;
+
+ conn->copy_raw_mode = format == 2;
}
/* Success! */
@@ -1544,13 +1546,38 @@ pqGetCopyData3(PGconn *conn, char **buffer, int async)
libpq_gettext("out of memory\n"));
return -2;
}
- memcpy(*buffer, &conn->inBuffer[conn->inCursor], msgLength);
- (*buffer)[msgLength] = '\0'; /* Add terminating null */
- /* Mark message consumed */
- conn->inStart = conn->inCursor + msgLength;
+ if (!conn->copy_raw_mode)
+ {
+ memcpy(*buffer, &conn->inBuffer[conn->inCursor], msgLength);
+ (*buffer)[msgLength] = '\0'; /* Add terminating null */
- return msgLength;
+ conn->inStart = conn->inCursor + msgLength;
+
+ return msgLength;
+ }
+ else
+ {
+ if (msgLength < 4)
+ {
+ printfPQExpBuffer(&conn->errorMessage,
+ libpq_gettext("broken format\n"));
+ return -2;
+ }
+
+ /*
+ * raw format is same as binary without addtional info. Every
+ * binary data starts with length 4B
+ */
+ memcpy(*buffer, &conn->inBuffer[conn->inCursor + 4], msgLength - 4);
+ (*buffer)[msgLength] = '\0'; /* Add terminating null */
+
+ conn->inStart = conn->inCursor + msgLength;
+
+ return msgLength - 4;
+ }
+
+ /* Mark message consumed */
}
/* Empty, so drop it and loop around for another */
diff --git a/src/interfaces/libpq/libpq-int.h b/src/interfaces/libpq/libpq-int.h
index 2175957..23bde61 100644
--- a/src/interfaces/libpq/libpq-int.h
+++ b/src/interfaces/libpq/libpq-int.h
@@ -421,6 +421,8 @@ struct pg_conn
PGresult *result; /* result being constructed */
PGresult *next_result; /* next result (used in single-row mode) */
+ bool copy_raw_mode; /* true, when one value is passed by copy protocol */
+
/* Assorted state for SSL, GSS, etc */
#ifdef USE_SSL
--
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