ECPG cursor examples should include EXEC SQL WHENEVER NOT FOUND CONTINUE; after the while loop

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To: pgsql-docs(at)lists(dot)postgresql(dot)org
Cc: andrew(at)andrewculver(dot)com
Subject: ECPG cursor examples should include EXEC SQL WHENEVER NOT FOUND CONTINUE; after the while loop
Date: 2021-07-03 11:54:11
Message-ID: 162531325118.701.13401788614496956581@wrigleys.postgresql.org
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The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/13/ecpg-variables.html
Description:

Without this line:
EXEC SQL WHENEVER NOT FOUND CONTINUE;
after the while(1), I find that ECPG CURSOR examples fail.

For example, this example under 36.4.4.3.2. Structures fails:

EXEC SQL BEGIN DECLARE SECTION;
typedef struct
{
int oid;
char datname[65];
long long int size;
} dbinfo_t;

dbinfo_t dbval;
EXEC SQL END DECLARE SECTION;

memset(&dbval, 0, sizeof(dbinfo_t));

EXEC SQL DECLARE cur1 CURSOR FOR SELECT oid, datname,
pg_database_size(oid) AS size FROM pg_database;
EXEC SQL OPEN cur1;

/* when end of result set reached, break out of while loop */
EXEC SQL WHENEVER NOT FOUND DO BREAK;

while (1)
{
/* Fetch multiple columns into one structure. */
EXEC SQL FETCH FROM cur1 INTO :dbval;

/* Print members of the structure. */
printf("oid=%d, datname=%s, size=%lld\n", dbval.oid, dbval.datname,
dbval.size);
}

EXEC SQL CLOSE cur1;

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