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Do not dump Babelfish initialize user (#216)
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When Babelfish initialize user is same between source and target servers for dump/restore, the restore throws errors like "role ... already exists" and "duplicate key value violates unique constraint..." etc while inserting catalog entry for initialize user in babelfish_authid_login_ext catalog. These errors are actually expected and makes sense as we know the user do already exists on the target server but the whole restore gets rolled back in case the restore process has been made transactional (`--single-transaction` option is used) and there is no way for a user to fix this manually.

To overcome the above issue, this commit implements the logic to skip dumping Babelfish initialize user so that there is no conflict when initialize user is same or different between source and target servers. This is safe since no T-SQL objects will have direct reference to initialize user and they will adapt to the new initialize user on the target server.

The only case we have to handle is the "owner" name in `sys.babelfish_sysdatabases` catalog table, which references to initialize user. For this, we will also skip dumping the "owner" column and re-populate this column during restore with the owner of current database (which is going to be initialize user of target Babelfish database).

Task: BABEL-4404 
Signed-off-by: Rishabh Tanwar <[email protected]>

Extensions PR: babelfish-for-postgresql/babelfish_extensions#1841
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@rishabhtanwar29
rishabhtanwar29 authored Sep 19, 2023
1 parent d060983 commit a211b57
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Showing 3 changed files with 99 additions and 26 deletions.
66 changes: 49 additions & 17 deletions src/bin/pg_dump/dump_babel_utils.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -35,6 +35,7 @@ static const CatalogId nilCatalogId = {0, 0};
static char *escaped_bbf_db_name = NULL;
static int bbf_db_id = 0;
static SimpleOidList catalog_table_include_oids = {NULL, NULL};
static char *babel_init_user = NULL;

static char *getMinOid(Archive *fout);
static bool isBabelfishConfigTable(TableInfo *tbinfo);
Expand Down Expand Up @@ -223,6 +224,7 @@ dumpBabelRestoreChecks(Archive *fout)
char *source_server_version;
char *source_migration_mode;
PQExpBuffer qry;
ArchiveFormat format = ((ArchiveHandle *) fout)->format;

/* Skip if not Babelfish database or binary upgrade */
if (!isBabelfishDatabase(fout) || fout->dopt->binary_upgrade)
Expand All @@ -241,8 +243,10 @@ dumpBabelRestoreChecks(Archive *fout)
/*
* Temporarily enable ON_ERROR_STOP so that whole restore script
* execution fails if the following do block raises an error.
* Note that it can only be used in plain text dump (archNull).
*/
appendPQExpBufferStr(qry, "\\set ON_ERROR_STOP on\n\n");
if (format == archNull)
appendPQExpBufferStr(qry, "\\set ON_ERROR_STOP on\n\n");
appendPQExpBuffer(qry,
"DO $$"
"\nDECLARE"
Expand Down Expand Up @@ -276,7 +280,8 @@ dumpBabelRestoreChecks(Archive *fout)
"\n END IF;"
"\nEND$$;\n\n"
, source_migration_mode);
appendPQExpBufferStr(qry, "\\set ON_ERROR_STOP off\n");
if (format == archNull)
appendPQExpBufferStr(qry, "\\set ON_ERROR_STOP off\n");
PQclear(res);

ArchiveEntry(fout, nilCatalogId, createDumpId(),
Expand Down Expand Up @@ -844,7 +849,7 @@ updateExtConfigArray(Archive *fout, char ***extconfigarray, int nconfigitems)
}

PQclear(res);
resetPQExpBuffer(query);
destroyPQExpBuffer(query);
}

/*
Expand Down Expand Up @@ -890,6 +895,19 @@ prepareForBabelfishDatabaseDump(Archive *fout, SimpleStringList *schema_include_
for (i = 0; i < ntups; i++)
simple_oid_list_append(&catalog_table_include_oids, atooid(PQgetvalue(res, i, 0)));

PQclear(res);
resetPQExpBuffer(query);

/*
* Find out initialize user of current Babelfish database
* which is essentially same as owner of the database.
*/
appendPQExpBufferStr(query, "SELECT r.rolname FROM pg_roles r "
"INNER JOIN pg_database d ON r.oid = d.datdba "
"WHERE d.datname = current_database()");
res = ExecuteSqlQueryForSingleRow(fout, query->data);
babel_init_user = pstrdup(PQgetvalue(res, 0, 0));

PQclear(res);
destroyPQExpBuffer(query);

Expand Down Expand Up @@ -1090,8 +1108,8 @@ addFromClauseForPhysicalDatabaseDump(PQExpBuffer buf, TableInfo *tbinfo)
}
else if(strcmp(tbinfo->dobj.name, "babelfish_authid_login_ext") == 0)
appendPQExpBuffer(buf, " FROM ONLY %s a "
"WHERE a.rolname!='sysadmin'",
fmtQualifiedDumpable(tbinfo));
"WHERE a.rolname NOT IN ('sysadmin', '%s')", /* Do not dump sysadmin and Babelfish initialize user */
fmtQualifiedDumpable(tbinfo), babel_init_user);
else if(strcmp(tbinfo->dobj.name, "babelfish_domain_mapping") == 0 ||
strcmp(tbinfo->dobj.name, "babelfish_function_ext") == 0 ||
strcmp(tbinfo->dobj.name, "babelfish_view_def") == 0 ||
Expand All @@ -1117,6 +1135,7 @@ fixCursorForBbfCatalogTableData(Archive *fout, TableInfo *tbinfo, PQExpBuffer bu
int i;
bool is_builtin_db = false;
bool is_bbf_usr_ext_tab = false;
bool is_bbf_sysdatabases_tab = false;

/*
* Return if not a Babelfish database, or if the table is not a Babelfish
Expand All @@ -1132,9 +1151,11 @@ fixCursorForBbfCatalogTableData(Archive *fout, TableInfo *tbinfo, PQExpBuffer bu
pg_strcasecmp(bbf_db_name, "msdb") == 0)
? true : false;

/* Remember if it is babelfish_authid_user_ext catalog table. */
/* Remember if it is babelfish_authid_user_ext and babelfish_sysdatabases catalog table. */
if (strcmp(tbinfo->dobj.name, "babelfish_authid_user_ext") == 0)
is_bbf_usr_ext_tab = true;
if (strcmp(tbinfo->dobj.name, "babelfish_sysdatabases") == 0)
is_bbf_sysdatabases_tab = true;

resetPQExpBuffer(buf);
appendPQExpBufferStr(buf, "DECLARE _pg_dump_cursor CURSOR FOR SELECT ");
Expand All @@ -1153,6 +1174,13 @@ fixCursorForBbfCatalogTableData(Archive *fout, TableInfo *tbinfo, PQExpBuffer bu
*/
if (bbf_db_name != NULL && !is_builtin_db && strcmp(tbinfo->attnames[i], "dbid") == 0)
continue;
/*
* We need to skip owner column of babelfish_sysdatabases table as it might be
* referencing Babelfish initialize user which we do not include in dump. We will
* populate this column during restore with the initialize user of target database.
*/
else if (is_bbf_sysdatabases_tab && strcmp(tbinfo->attnames[i], "owner") == 0)
continue;
if (*nfields > 0)
appendPQExpBufferStr(buf, ", ");
/*
Expand Down Expand Up @@ -1196,6 +1224,7 @@ fixCopyCommand(Archive *fout, PQExpBuffer copyBuf, TableInfo *tbinfo, bool isFro
bool is_builtin_db = false;
bool needComma = false;
bool is_bbf_usr_ext_tab = false;
bool is_bbf_sysdatabases_tab = false;

/*
* Return if not a Babelfish database, or if the table is not a Babelfish
Expand All @@ -1210,9 +1239,11 @@ fixCopyCommand(Archive *fout, PQExpBuffer copyBuf, TableInfo *tbinfo, bool isFro
pg_strcasecmp(bbf_db_name, "msdb") == 0)
? true : false;

/* Remember if it is babelfish_authid_user_ext catalog table. */
/* Remember if it is babelfish_authid_user_ext and babelfish_sysdatabases catalog table. */
if (strcmp(tbinfo->dobj.name, "babelfish_authid_user_ext") == 0)
is_bbf_usr_ext_tab = true;
if (strcmp(tbinfo->dobj.name, "babelfish_sysdatabases") == 0)
is_bbf_sysdatabases_tab = true;

q = createPQExpBuffer();
for (i = 0; i < tbinfo->numatts; i++)
Expand All @@ -1228,6 +1259,13 @@ fixCopyCommand(Archive *fout, PQExpBuffer copyBuf, TableInfo *tbinfo, bool isFro
*/
if (bbf_db_name != NULL && !is_builtin_db && strcmp(tbinfo->attnames[i], "dbid") == 0)
continue;
/*
* We need to skip owner column of babelfish_sysdatabases table as it might be
* referencing Babelfish initialize user which we do not include in dump. We will
* populate this column during restore with the initialize user of target database.
*/
else if (is_bbf_sysdatabases_tab && strcmp(tbinfo->attnames[i], "owner") == 0)
continue;
if (needComma)
appendPQExpBufferStr(q, ", ");

Expand Down Expand Up @@ -1278,19 +1316,13 @@ fixCopyCommand(Archive *fout, PQExpBuffer copyBuf, TableInfo *tbinfo, bool isFro
* Returns true if table in Babelfish Database is to be dumped with INSERT mode.
* Currently we dump tables with sql_variant columns with INSERT operations to
* correctly restore the metadata of the base datatype, which is not directly
* posible with COPY statements. We also dump sys.babelfish_authid_login_ext
* with INSERT statements so that if target database already has a login with
* same name as in the source database, only that INSERT query with fail and won't
* affect the other entries of the catalog table.
* possible with COPY statements.
*/
bool bbfIsDumpWithInsert(Archive *fout, TableInfo *tbinfo)
bool
bbfIsDumpWithInsert(Archive *fout, TableInfo *tbinfo)
{
return (isBabelfishDatabase(fout) &&
(hasSqlvariantColumn(tbinfo) ||
pg_strcasecmp(fmtQualifiedDumpable(tbinfo),
quote_all_identifiers ?
"\"sys\".\"babelfish_authid_login_ext\"" :
"sys.babelfish_authid_login_ext") == 0));
hasSqlvariantColumn(tbinfo));
}

/*
Expand Down
52 changes: 47 additions & 5 deletions src/bin/pg_dump/dumpall_babel_utils.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -58,6 +58,30 @@ executeQuery(PGconn *conn, const char *query)
return res;
}

/*
* getBabelfishInitUser
* Returns initialize user of current Babelfish database
* which is essentially same as owner of the database.
*/
static char *
getBabelfishInitUser(PGconn *conn)
{
PQExpBuffer qry;
PGresult *res;
char *babel_init_user;

qry = createPQExpBuffer();
appendPQExpBufferStr(qry, "SELECT r.rolname FROM pg_roles r "
"INNER JOIN pg_database d ON r.oid = d.datdba "
"WHERE d.datname = current_database()");
res = executeQuery(conn, qry->data);
babel_init_user = pstrdup(PQgetvalue(res, 0, 0));
PQclear(res);
destroyPQExpBuffer(qry);

return babel_init_user;
}

/*
* isBabelfishDatabase:
* returns true if current database has "babelfishpg_tsql"
Expand Down Expand Up @@ -172,10 +196,21 @@ getBabelfishRolesQuery(PGconn *conn, PQExpBuffer buf, char *role_catalog,

resetPQExpBuffer(buf);
appendPQExpBufferStr(buf, "WITH bbf_catalog AS (");
/* Include logins only in case of Babelfish physical database dump. */
/*
* Include logins only in case of Babelfish physical database dump.
* Note that we will not dump Babelfish initialize user as it might
* already be present on the target server.
*/
if (!bbf_db_name)
appendPQExpBufferStr(buf,
"SELECT rolname FROM sys.babelfish_authid_login_ext UNION ");
{
char *babel_init_user = getBabelfishInitUser(conn);
appendPQExpBuffer(buf,
"SELECT rolname FROM sys.babelfish_authid_login_ext "
"WHERE rolname != '%s' " /* Do not dump Babelfish initialize user */
"UNION ",
babel_init_user);
pfree(babel_init_user);
}
appendPQExpBufferStr(buf,
"SELECT rolname FROM sys.babelfish_authid_user_ext ");
/* Only dump users of the specific logical database we are currently dumping. */
Expand Down Expand Up @@ -241,8 +276,15 @@ getBabelfishRoleMembershipQuery(PGconn *conn, PQExpBuffer buf,
appendPQExpBufferStr(buf, "WITH bbf_catalog AS (");
/* Include logins only in case of Babelfish physical database dump. */
if (!bbf_db_name)
appendPQExpBufferStr(buf,
"SELECT rolname FROM sys.babelfish_authid_login_ext UNION ");
{
char *babel_init_user = getBabelfishInitUser(conn);
appendPQExpBuffer(buf,
"SELECT rolname FROM sys.babelfish_authid_login_ext "
"WHERE rolname != '%s' " /* Do not dump Babelfish initialize user */
"UNION ",
babel_init_user);
pfree(babel_init_user);
}
appendPQExpBuffer(buf,
"SELECT rolname FROM sys.babelfish_authid_user_ext ");
/* Only dump users of the specific logical database we are currently dumping. */
Expand Down
7 changes: 3 additions & 4 deletions src/bin/pg_dump/pg_dump.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -2149,8 +2149,7 @@ dumpTableData_insert(Archive *fout, const void *dcontext)
int rows_this_statement = 0;

/*
* For tables in Babelfish Database with sql_variant datatype columns and
* sys.babelfish_authid_login_ext Babelfish catalog table, we want to
* For tables in Babelfish Database with sql_variant datatype columns, we want to
* surpass dopt->column_inserts check since these tables need to be dumped
* as when column_inserts is true.
*/
Expand Down Expand Up @@ -2544,8 +2543,8 @@ dumpTableData(Archive *fout, const TableDataInfo *tdinfo)
if (bbfIsDumpWithInsert(fout, tbinfo))
{
/*
* dump tables in Babelfish Database with sql_variant datatype columns and
* sys.babelfish_authid_login_ext Babelfish catalog table using INSERT only
* dump tables in Babelfish Database with sql_variant
* datatype columns using INSERT only.
*/
dumpFn = dumpTableData_insert;
copyStmt = NULL;
Expand Down

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