NotificationsYou must be signed in to change notification settings
Fork6
Star31

Commit10b5f0b

committed

Here's a small patch for dblink:

- fixed dblink invalid pointer causing corrupt elog message - fixed dblink_tok improper handling of null results - fixed examples in README.dblinkJoe Conway

1 parentec96f1d commit10b5f0bCopy full SHA for 10b5f0b

File tree

2 files changed

+33

-19

lines changed

contrib/dblink
- README.dblink
- dblink.c

2 files changed

+33

-19

lines changed

`‎contrib/dblink/README.dblink`

Lines changed: 12 additions & 6 deletions

Original file line number	Diff line number	Diff line change
`@@ -24,12 +24,18 @@`
`24`	`24`	`*`
`25`	`25`	`*/`
`26`	`26`
`27`		`-Version 0.2 (29 May, 2001):`
	`27`	`+`
	`28`	`+Version 0.3 (14 June, 2001):`
`28`	`29`	`Function to test returning data set from remote database`
`29`	`30`	`Tested under Linux (Red Hat 6.2 and 7.0) and PostgreSQL 7.1 and 7.2devel`
`30`	`31`
`31`	`32`	`Release Notes:`
`32`	`33`
	`34`	`+ Version 0.3`
	`35`	`+ - fixed dblink invalid pointer causing corrupt elog message`
	`36`	`+ - fixed dblink_tok improper handling of null results`
	`37`	`+ - fixed examples in README.dblink`
	`38`	`+`
`33`	`39`	`Version 0.2`
`34`	`40`	`- initial release`
`35`	`41`
`@@ -124,11 +130,11 @@ to 'fake' a UNION, e.g.`
`124`	`130`	`'hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'`
`125`	`131`	`,'select f1, f2 from mytable'`
`126`	`132`	`) as dblink_p`
`127`		`- union`
`128`		`- select null,null where false`
	`133`	`+ union all`
	`134`	`+ select null where false`
`129`	`135`	`) as t1`
`130`	`136`	`where`
`131`		`-f1 = 'mycriteria';`
	`137`	`+dblink_tok(t1.dblink_p,0) = 'mycriteria';`
`132`	`138`
`133`	`139`	`in order to work around an issue with the query optimizer. A more convenient way to approach`
`134`	`140`	`this problem is to create a view:`
`@@ -143,8 +149,8 @@ this problem is to create a view:`
`143`	`149`	`'hostaddr=127.0.0.1 port=5432 dbname=mydb user=postgres password=mypasswd'`
`144`	`150`	`,'select f1, f2 from mytable'`
`145`	`151`	`) as dblink_p`
`146`		`- union`
`147`		`- select null,null where false`
	`152`	`+ union all`
	`153`	`+ select null where false`
`148`	`154`	`) as t1;`
`149`	`155`
`150`	`156`	`Then you can simply write:`

`‎contrib/dblink/dblink.c`

Lines changed: 21 additions & 13 deletions

Original file line number	Diff line number	Diff line change
`@@ -57,15 +57,15 @@ dblink(PG_FUNCTION_ARGS)`
`57`	`57`	`conn=PQconnectdb(optstr);`
`58`	`58`	`if (PQstatus(conn)==CONNECTION_BAD)`
`59`	`59`	`{`
`60`		`-msg=PQerrorMessage(conn);`
	`60`	`+msg=pstrdup(PQerrorMessage(conn));`
`61`	`61`	`PQfinish(conn);`
`62`	`62`	`elog(ERROR,"dblink: connection error: %s",msg);`
`63`	`63`	`}`
`64`	`64`
`65`	`65`	`res=PQexec(conn,"BEGIN");`
`66`	`66`	`if (PQresultStatus(res)!=PGRES_COMMAND_OK)`
`67`	`67`	`{`
`68`		`-msg=PQerrorMessage(conn);`
	`68`	`+msg=pstrdup(PQerrorMessage(conn));`
`69`	`69`	`PQclear(res);`
`70`	`70`	`PQfinish(conn);`
`71`	`71`	`elog(ERROR,"dblink: begin error: %s",msg);`
`@@ -84,7 +84,7 @@ dblink(PG_FUNCTION_ARGS)`
`84`	`84`	`res=PQexec(conn,execstatement);`
`85`	`85`	`if (!res\|\| (PQresultStatus(res)!=PGRES_COMMAND_OK&&PQresultStatus(res)!=PGRES_TUPLES_OK))`
`86`	`86`	`{`
`87`		`-msg=PQerrorMessage(conn);`
	`87`	`+msg=pstrdup(PQerrorMessage(conn));`
`88`	`88`	`PQclear(res);`
`89`	`89`	`PQfinish(conn);`
`90`	`90`	`elog(ERROR,"dblink: sql error: %s",msg);`
`@@ -96,7 +96,7 @@ dblink(PG_FUNCTION_ARGS)`
`96`	`96`
`97`	`97`	`res=PQexec(conn,"FETCH ALL in mycursor");`
`98`	`98`	`if (!res\|\|PQresultStatus(res)!=PGRES_TUPLES_OK) {`
`99`		`-msg=PQerrorMessage(conn);`
	`99`	`+msg=pstrdup(PQerrorMessage(conn));`
`100`	`100`	`PQclear(res);`
`101`	`101`	`PQfinish(conn);`
`102`	`102`	`elog(ERROR,"dblink: sql error: %s",msg);`
`@@ -230,20 +230,28 @@ dblink_tok(PG_FUNCTION_ARGS)`
`230`	`230`	`elog(ERROR,"dblink: field number %d does not exist",fldnum);`
`231`	`231`	`}`
`232`	`232`
`233`		`-text_len=PQgetlength(results->res,results->tup_num,fldnum);`
	`233`	`+if (PQgetisnull(results->res,results->tup_num,fldnum)==1) {`
`234`	`234`
`235`		`-result= (char*)palloc(text_len+1);`
	`235`	`+PG_RETURN_NULL();`
`236`	`236`
`237`		`-if (result!=NULL) {`
`238`		`-strcpy(result,PQgetvalue(results->res,results->tup_num,fldnum));`
`239`		`-strcat(result,"\0");`
`240`	`237`	`}else {`
`241`		`-elog(ERROR,"dblink: insufficient memory" );`
`242`		`-}`
`243`	`238`
`244`		`-result_text=DatumGetTextP(DirectFunctionCall1(textin,CStringGetDatum(result)));`
	`239`	`+text_len=PQgetlength(results->res,results->tup_num,fldnum);`
	`240`	`+`
	`241`	`+result= (char*)palloc(text_len+1);`
`245`	`242`
`246`		`-PG_RETURN_TEXT_P(result_text);`
	`243`	`+if (result!=NULL) {`
	`244`	`+strcpy(result,PQgetvalue(results->res,results->tup_num,fldnum));`
	`245`	`+strcat(result,"\0");`
	`246`	`+}else {`
	`247`	`+elog(ERROR,"dblink: insufficient memory" );`
	`248`	`+}`
	`249`	`+`
	`250`	`+result_text=DatumGetTextP(DirectFunctionCall1(textin,CStringGetDatum(result)));`
	`251`	`+`
	`252`	`+PG_RETURN_TEXT_P(result_text);`
	`253`	`+`
	`254`	`+}`
`247`	`255`	`}`
`248`	`256`
`249`	`257`

0 commit comments

Comments

(0)

Movatterモバイル変換

Navigation Menu

Search code, repositories, users, issues, pull requests...

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Commit10b5f0b

File tree

2 files changed

2 files changed

`‎contrib/dblink/README.dblink`

`‎contrib/dblink/dblink.c`

0 commit comments