Fixes additional compile errors

create_drop_db_gh
gindibay 2023-09-23 03:09:06 +03:00
parent 226696e42a
commit ae9cd9c895
6 changed files with 826 additions and 0 deletions

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#include "distributed/metadata/distobject.h"
#include "distributed/database/database_sharding.h"
#include "distributed/deparse_shard_query.h"
#include "distributed/listutils.h"
#include "distributed/adaptive_executor.h"

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/*-------------------------------------------------------------------------
*
* database_lock.c
* Functions for locking a database.
*
* Copyright (c) Microsoft, Inc.
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "funcapi.h"
#include "fmgr.h"
#include "miscadmin.h"
#include "catalog/pg_database.h"
#include "commands/dbcommands.h"
#include "distributed/metadata_cache.h"
#include "storage/lmgr.h"
static void CitusDatabaseLock(Oid databaseId);
PG_FUNCTION_INFO_V1(citus_database_lock_by_name);
/*
* citus_database_lock locks the given database in access exclusive mode
* to temporarily block new connections.
*/
Datum
citus_database_lock_by_name(PG_FUNCTION_ARGS)
{
CheckCitusVersion(ERROR);
Name databaseName = PG_GETARG_NAME(0);
bool missingOk = false;
Oid databaseId = get_database_oid(NameStr(*databaseName), missingOk);
CitusDatabaseLock(databaseId);
PG_RETURN_VOID();
}
/*
* CitusDatabaseLock locks a database for new connections.
*/
static void
CitusDatabaseLock(Oid databaseId)
{
LockSharedObject(DatabaseRelationId, databaseId, 0, ExclusiveLock);
}

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/*-------------------------------------------------------------------------
*
* database_sharding.c
*
* This file contains module-level definitions.
*
* Copyright (c) 2023, Microsoft, Inc.
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "fmgr.h"
#include "miscadmin.h"
#include "citus_version.h"
#include "pg_version_compat.h"
#include "access/genam.h"
#include "commands/dbcommands.h"
#include "distributed/connection_management.h"
#include "distributed/database/database_sharding.h"
#include "distributed/deparser.h"
#include "distributed/deparse_shard_query.h"
#include "distributed/listutils.h"
#include "distributed/metadata_sync.h"
#include "distributed/remote_commands.h"
#include "distributed/shared_library_init.h"
#include "distributed/worker_transaction.h"
#include "executor/spi.h"
#include "nodes/makefuncs.h"
#include "nodes/parsenodes.h"
#include "postmaster/postmaster.h"
#include "tcop/utility.h"
#include "utils/builtins.h"
#include "utils/fmgroids.h"
static void ExecuteCommandInControlDatabase(char *command);
static void AllowConnectionsOnlyOnNodeGroup(Oid databaseOid, Oid nodeGroupId);
static void InsertDatabaseShardAssignment(Oid databaseOid, int nodeGroupId);
static void InsertDatabaseShardAssignmentLocally(Oid databaseOid, int nodeGroupId);
static void InsertDatabaseShardAssignmentOnOtherNodes(Oid databaseOid, int nodeGroupId);
static void DeleteDatabaseShardByDatabaseId(Oid databaseOid);
static void DeleteDatabaseShardByDatabaseIdOnOtherNodes(Oid databaseOid);
static DatabaseShard * TupleToDatabaseShard(HeapTuple heapTuple,
TupleDesc tupleDescriptor);
static char * DeleteDatabaseShardByDatabaseIdCommand(Oid databaseOid);
PG_FUNCTION_INFO_V1(database_shard_assign);
PG_FUNCTION_INFO_V1(citus_internal_add_database_shard);
PG_FUNCTION_INFO_V1(citus_internal_delete_database_shard);
/* citus.enable_database_sharding setting */
bool EnableDatabaseSharding = false;
/* citus.database_sharding_pgbouncer_file setting */
char *DatabaseShardingPgBouncerFile = "";
/*
* PreProcessUtilityInDatabaseShard handles DDL commands that occur within a
* database shard and require global coordination:
* - CREATE/ALTER/DROP DATABASE
* - CREATE/ALTER/DROP ROLE/USER/GROUP
*/
void
PreProcessUtilityInDatabaseShard(Node *parseTree, const char *queryString,
ProcessUtilityContext context,
bool *runPreviousUtilityHook)
{
if (!EnableDatabaseSharding || context != PROCESS_UTILITY_TOPLEVEL)
{
return;
}
if (EnableCreateDatabasePropagation)
{
if (IsA(parseTree, CreatedbStmt))
{
char *command = DeparseCreatedbStmt(parseTree);
ExecuteCommandInControlDatabase(command);
/* command is fully delegated to control database */
*runPreviousUtilityHook = false;
}
else if (IsA(parseTree, DropdbStmt))
{
char *command = DeparseDropdbStmt(parseTree);
ExecuteCommandInControlDatabase(command);
/* command is fully delegated to control database */
*runPreviousUtilityHook = false;
}
}
}
/*
* PostProcessUtilityInDatabaseShard is currently a noop.
*/
void
PostProcessUtilityInDatabaseShard(Node *parseTree, const char *queryString,
ProcessUtilityContext context)
{
if (!EnableDatabaseSharding || context != PROCESS_UTILITY_TOPLEVEL)
{
return;
}
}
/*
* ExecuteCommandInControlDatabase connects to localhost to execute a command
* in the main Citus database.
*/
static void
ExecuteCommandInControlDatabase(char *command)
{
int connectionFlag = FORCE_NEW_CONNECTION;
MultiConnection *connection =
GetNodeUserDatabaseConnection(connectionFlag, LocalHostName, PostPortNumber,
NULL, CitusMainDatabase);
ExecuteCriticalRemoteCommand(connection,
"SET application_name TO 'citus_database_shard'");
ExecuteCriticalRemoteCommand(connection, command);
CloseConnection(connection);
}
/*
* database_shard_assign assigns an existing database to a node.
*/
Datum
database_shard_assign(PG_FUNCTION_ARGS)
{
CheckCitusVersion(ERROR);
char *databaseName = text_to_cstring(PG_GETARG_TEXT_P(0));
bool missingOk = false;
Oid databaseOid = get_database_oid(databaseName, missingOk);
if (!pg_database_ownercheck(databaseOid, GetUserId()))
{
ereport(ERROR, (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
errmsg("permission denied to assign database \"%s\" "
"to a shard",
databaseName)));
}
if (GetDatabaseShardByOid(databaseOid) != NULL)
{
ereport(ERROR, (errmsg("database is already assigned to a shard")));
}
AssignDatabaseToShard(databaseOid);
PG_RETURN_VOID();
}
/*
* AssignDatabaseToShard finds a suitable node for the given
* database and assigns it.
*/
void
AssignDatabaseToShard(Oid databaseOid)
{
int nodeGroupId = GetLocalGroupId();
List *workerNodes = TargetWorkerSetNodeList(ALL_SHARD_NODES, RowShareLock);
if (list_length(workerNodes) > 0)
{
/* TODO: actually look for available space */
int workerNodeIndex = databaseOid % list_length(workerNodes);
WorkerNode *workerNode = list_nth(workerNodes, workerNodeIndex);
nodeGroupId = workerNode->groupId;
}
InsertDatabaseShardAssignment(databaseOid, nodeGroupId);
AllowConnectionsOnlyOnNodeGroup(databaseOid, nodeGroupId);
ReconfigurePgBouncersOnCommit = true;
}
/*
* AllowConnectionsOnlyOnNodeGroup sets the ALLOW_CONNECTIONS properties on
* the database to false, except on nodeGroupId.
*/
static void
AllowConnectionsOnlyOnNodeGroup(Oid databaseOid, Oid nodeGroupId)
{
StringInfo command = makeStringInfo();
char *databaseName = get_database_name(databaseOid);
List *workerNodes = TargetWorkerSetNodeList(ALL_SHARD_NODES, RowShareLock);
WorkerNode *workerNode = NULL;
foreach_ptr(workerNode, workerNodes)
{
resetStringInfo(command);
if (workerNode->groupId == nodeGroupId)
{
appendStringInfo(command, "GRANT CONNECT ON DATABASE %s TO public",
quote_identifier(databaseName));
}
else
{
appendStringInfo(command, "REVOKE CONNECT ON DATABASE %s FROM public",
quote_identifier(databaseName));
}
if (workerNode->groupId == GetLocalGroupId())
{
ExecuteQueryViaSPI(command->data, SPI_OK_UTILITY);
}
else
{
SendCommandToWorker(workerNode->workerName, workerNode->workerPort,
command->data);
}
}
}
/*
* InsertDatabaseShardAssignment inserts a record into the local
* citus_catalog.database_sharding table.
*/
static void
InsertDatabaseShardAssignment(Oid databaseOid, int nodeGroupId)
{
InsertDatabaseShardAssignmentLocally(databaseOid, nodeGroupId);
if (EnableMetadataSync)
{
InsertDatabaseShardAssignmentOnOtherNodes(databaseOid, nodeGroupId);
}
}
/*
* InsertDatabaseShardAssignmentLocally inserts a record into the local
* citus_catalog.database_sharding table.
*/
static void
InsertDatabaseShardAssignmentLocally(Oid databaseOid, int nodeGroupId)
{
Datum values[Natts_database_shard];
bool isNulls[Natts_database_shard];
/* form new shard tuple */
memset(values, 0, sizeof(values));
memset(isNulls, false, sizeof(isNulls));
values[Anum_database_shard_database_id - 1] = ObjectIdGetDatum(databaseOid);
values[Anum_database_shard_node_group_id - 1] = Int32GetDatum(nodeGroupId);
values[Anum_database_shard_is_available - 1] = BoolGetDatum(true);
/* open shard relation and insert new tuple */
Relation databaseShardTable = table_open(DatabaseShardRelationId(), RowExclusiveLock);
TupleDesc tupleDescriptor = RelationGetDescr(databaseShardTable);
HeapTuple heapTuple = heap_form_tuple(tupleDescriptor, values, isNulls);
CatalogTupleInsert(databaseShardTable, heapTuple);
CommandCounterIncrement();
table_close(databaseShardTable, NoLock);
}
/*
* InsertDatabaseShardAssignmentOnOtherNodes inserts a record into the
* citus_catalog.database_sharding table on other nodes.
*/
static void
InsertDatabaseShardAssignmentOnOtherNodes(Oid databaseOid, int nodeGroupId)
{
char *insertCommand = InsertDatabaseShardAssignmentCommand(databaseOid, nodeGroupId);
SendCommandToWorkersWithMetadata(insertCommand);
}
/*
* UpdateDatabaseShard updates a database shard after it is moved to a new node.
*/
void
UpdateDatabaseShard(Oid databaseOid, int targetNodeGroupId)
{
DeleteDatabaseShardByDatabaseId(databaseOid);
InsertDatabaseShardAssignment(databaseOid, targetNodeGroupId);
AllowConnectionsOnlyOnNodeGroup(databaseOid, targetNodeGroupId);
}
/*
* DeleteDatabaseShardByDatabaseId deletes a record from the
* citus_catalog.database_sharding table.
*/
static void
DeleteDatabaseShardByDatabaseId(Oid databaseOid)
{
DeleteDatabaseShardByDatabaseIdLocally(databaseOid);
if (EnableMetadataSync)
{
DeleteDatabaseShardByDatabaseIdOnOtherNodes(databaseOid);
}
}
/*
* DeleteDatabaseShardByDatabaseIdLocally deletes a database_shard record by database OID.
*/
void
DeleteDatabaseShardByDatabaseIdLocally(Oid databaseOid)
{
Relation databaseShardTable = table_open(DatabaseShardRelationId(),
RowExclusiveLock);
const int scanKeyCount = 1;
ScanKeyData scanKey[1];
bool indexOK = true;
ScanKeyInit(&scanKey[0], Anum_database_shard_database_id,
BTEqualStrategyNumber, F_OIDEQ, ObjectIdGetDatum(databaseOid));
SysScanDesc scanDescriptor = systable_beginscan(databaseShardTable,
DatabaseShardPrimaryKeyIndexId(),
indexOK,
NULL, scanKeyCount, scanKey);
HeapTuple heapTuple = systable_getnext(scanDescriptor);
if (heapTuple != NULL)
{
simple_heap_delete(databaseShardTable, &heapTuple->t_self);
}
systable_endscan(scanDescriptor);
CommandCounterIncrement();
table_close(databaseShardTable, NoLock);
}
/*
* DeleteDatabaseShardByDatabaseIdOnOtherNodes deletes a record from the
* citus_catalog.database_sharding table on other nodes.
*/
static void
DeleteDatabaseShardByDatabaseIdOnOtherNodes(Oid databaseOid)
{
char *deleteCommand = DeleteDatabaseShardByDatabaseIdCommand(databaseOid);
SendCommandToWorkersWithMetadata(deleteCommand);
}
/*
* ListDatabaseShards lists all database shards in citus_catalog.database_shard.
*/
List *
ListDatabaseShards(void)
{
Relation databaseShardTable = table_open(DatabaseShardRelationId(), AccessShareLock);
TupleDesc tupleDescriptor = RelationGetDescr(databaseShardTable);
List *dbShardList = NIL;
int scanKeyCount = 0;
bool indexOK = false;
SysScanDesc scanDescriptor = systable_beginscan(databaseShardTable, InvalidOid,
indexOK, NULL, scanKeyCount, NULL);
HeapTuple heapTuple = NULL;
while (HeapTupleIsValid(heapTuple = systable_getnext(scanDescriptor)))
{
DatabaseShard *dbShard = TupleToDatabaseShard(heapTuple, tupleDescriptor);
dbShardList = lappend(dbShardList, dbShard);
}
systable_endscan(scanDescriptor);
table_close(databaseShardTable, NoLock);
return dbShardList;
}
/*
* GetDatabaseShardByOid gets a database shard by database OID or
* NULL if no database shard could be found.
*/
DatabaseShard *
GetDatabaseShardByOid(Oid databaseOid)
{
DatabaseShard *result = NULL;
Relation databaseShardTable = table_open(DatabaseShardRelationId(), AccessShareLock);
TupleDesc tupleDescriptor = RelationGetDescr(databaseShardTable);
const int scanKeyCount = 1;
ScanKeyData scanKey[1];
bool indexOK = true;
ScanKeyInit(&scanKey[0], Anum_database_shard_database_id,
BTEqualStrategyNumber, F_OIDEQ, ObjectIdGetDatum(databaseOid));
SysScanDesc scanDescriptor = systable_beginscan(databaseShardTable,
DatabaseShardPrimaryKeyIndexId(),
indexOK,
NULL, scanKeyCount, scanKey);
HeapTuple heapTuple = systable_getnext(scanDescriptor);
if (HeapTupleIsValid(heapTuple))
{
result = TupleToDatabaseShard(heapTuple, tupleDescriptor);
}
systable_endscan(scanDescriptor);
table_close(databaseShardTable, NoLock);
return result;
}
/*
* TupleToDatabaseShard converts a database_shard record tuple into a DatabaseShard struct.
*/
static DatabaseShard *
TupleToDatabaseShard(HeapTuple heapTuple, TupleDesc tupleDescriptor)
{
Datum datumArray[Natts_database_shard];
bool isNullArray[Natts_database_shard];
heap_deform_tuple(heapTuple, tupleDescriptor, datumArray, isNullArray);
DatabaseShard *record = palloc0(sizeof(DatabaseShard));
record->databaseOid =
DatumGetObjectId(datumArray[Anum_database_shard_database_id - 1]);
record->nodeGroupId =
DatumGetInt32(datumArray[Anum_database_shard_node_group_id - 1]);
record->isAvailable =
DatumGetBool(datumArray[Anum_database_shard_is_available - 1]);
return record;
}
/*
* citus_internal_add_database_shard is an internal UDF to
* add a row to database_shard.
*/
Datum
citus_internal_add_database_shard(PG_FUNCTION_ARGS)
{
char *databaseName = TextDatumGetCString(PG_GETARG_DATUM(0));
int nodeGroupId = PG_GETARG_INT32(1);
bool missingOk = false;
Oid databaseOid = get_database_oid(databaseName, missingOk);
if (!pg_database_ownercheck(databaseOid, GetUserId()))
{
aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_DATABASE,
databaseName);
}
InsertDatabaseShardAssignmentLocally(databaseOid, nodeGroupId);
PG_RETURN_VOID();
}
/*
* InsertDatabaseShardAssignmentCommand returns a command to insert a database shard
* assignment into the metadata on a remote node.
*/
char *
InsertDatabaseShardAssignmentCommand(Oid databaseOid, int nodeGroupId)
{
StringInfo command = makeStringInfo();
char *databaseName = get_database_name(databaseOid);
appendStringInfo(command,
"SELECT pg_catalog.citus_internal_add_database_shard(%s,%d)",
quote_literal_cstr(databaseName),
nodeGroupId);
return command->data;
}
/*
* citus_internal_delete_database_shard is an internal UDF to
* delete a row from database_shard.
*/
Datum
citus_internal_delete_database_shard(PG_FUNCTION_ARGS)
{
char *databaseName = TextDatumGetCString(PG_GETARG_DATUM(0));
bool missingOk = false;
Oid databaseOid = get_database_oid(databaseName, missingOk);
if (!pg_database_ownercheck(databaseOid, GetUserId()))
{
aclcheck_error(ACLCHECK_NOT_OWNER, OBJECT_DATABASE,
databaseName);
}
DeleteDatabaseShardByDatabaseIdLocally(databaseOid);
PG_RETURN_VOID();
}
/*
* DeleteDatabaseShardByDatabaseIdCommand returns a command to delete a database shard
* assignment from the metadata on a remote node.
*/
static char *
DeleteDatabaseShardByDatabaseIdCommand(Oid databaseOid)
{
StringInfo command = makeStringInfo();
char *databaseName = get_database_name(databaseOid);
appendStringInfo(command,
"SELECT pg_catalog.citus_internal_delete_database_shard(%s)",
quote_literal_cstr(databaseName));
return command->data;
}

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/*-------------------------------------------------------------------------
*
* database_size.c
* Functions for getting the size of a database.
*
* Copyright (c) Microsoft, Inc.
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include "funcapi.h"
#include "fmgr.h"
#include "miscadmin.h"
#include "commands/dbcommands.h"
#include "distributed/citus_safe_lib.h"
#include "distributed/database/database_sharding.h"
#include "distributed/listutils.h"
#include "distributed/metadata_cache.h"
#include "distributed/remote_commands.h"
#include "distributed/worker_transaction.h"
#include "utils/builtins.h"
static int64 GetLocalDatabaseSize(Oid databaseId);
static int64 CitusDatabaseShardSize(DatabaseShard *dbShard);
static int64 CitusDatabaseSizeOnNodeList(Oid databaseId, List *workerNodeList);
PG_FUNCTION_INFO_V1(citus_database_size_oid);
PG_FUNCTION_INFO_V1(citus_database_size_name);
/*
* citus_database_size_oid returns the size of a Citus database
* with the given oid.
*/
Datum
citus_database_size_oid(PG_FUNCTION_ARGS)
{
CheckCitusVersion(ERROR);
Oid databaseId = PG_GETARG_OID(0);
int64 size = CitusDatabaseSize(databaseId);
PG_RETURN_INT64(size);
}
/*
* citus_database_size_name returns the size of a Citus database
* with the given name.
*/
Datum
citus_database_size_name(PG_FUNCTION_ARGS)
{
CheckCitusVersion(ERROR);
Name databaseName = PG_GETARG_NAME(0);
bool missingOk = false;
Oid databaseId = get_database_oid(NameStr(*databaseName), missingOk);
int64 size = CitusDatabaseSize(databaseId);
PG_RETURN_INT64(size);
}
/*
* CitusDatabaseSize returns the size of a Citus database.
*/
int64
CitusDatabaseSize(Oid databaseId)
{
DatabaseShard *dbShard = GetDatabaseShardByOid(databaseId);
if (dbShard != NULL)
{
/* for known database shards, get the remote size */
return CitusDatabaseShardSize(dbShard);
}
if (databaseId == MyDatabaseId)
{
/* for the current database, get the size from all nodes */
List *workerNodes = TargetWorkerSetNodeList(ALL_SHARD_NODES, RowShareLock);
return CitusDatabaseSizeOnNodeList(databaseId, workerNodes);
}
/* for other databases, get the local size */
/* TODO: get it from main database? */
return GetLocalDatabaseSize(databaseId);
}
/*
* GetLocalDatabaseSize returns the local database size by calling pg_database_size.
*/
static int64
GetLocalDatabaseSize(Oid databaseId)
{
Datum databaseIdDatum = ObjectIdGetDatum(databaseId);
Datum sizeDatum = DirectFunctionCall1(pg_database_size_oid, databaseIdDatum);
return DatumGetInt64(sizeDatum);
}
/*
* CitusDatabaseShardSize gets the database size for a specific
* shard.
*/
static int64
CitusDatabaseShardSize(DatabaseShard *dbShard)
{
WorkerNode *workerNode = LookupNodeForGroup(dbShard->nodeGroupId);
return CitusDatabaseSizeOnNodeList(dbShard->databaseOid, list_make1(workerNode));
}
/*
* CitusDatabaseSizeOnNodeList returns the sum of the sizes
* for a given database from all nodes in the list.
*/
static int64
CitusDatabaseSizeOnNodeList(Oid databaseId, List *workerNodeList)
{
int64 size = 0;
bool raiseInterrupts = true;
char *databaseName = get_database_name(databaseId);
char *command = psprintf("SELECT pg_catalog.pg_database_size(%s)",
quote_literal_cstr(databaseName));
WorkerNode *workerNode = NULL;
foreach_ptr(workerNode, workerNodeList)
{
if (workerNode->groupId == GetLocalGroupId())
{
return GetLocalDatabaseSize(databaseId);
}
int connectionFlags = 0;
MultiConnection *connection = GetNodeConnection(connectionFlags,
workerNode->workerName,
workerNode->workerPort);
int querySent = SendRemoteCommand(connection, command);
if (querySent == 0)
{
ReportConnectionError(connection, ERROR);
}
PGresult *result = GetRemoteCommandResult(connection, raiseInterrupts);
if (!IsResponseOK(result))
{
ReportResultError(connection, result, ERROR);
}
if (PQntuples(result) != 1 || PQnfields(result) != 1)
{
PQclear(result);
ClearResults(connection, raiseInterrupts);
ereport(ERROR, (errmsg("unexpected number of columns returned by: %s",
command)));
}
if (!PQgetisnull(result, 0, 0))
{
char *sizeString = PQgetvalue(result, 0, 0);
size += SafeStringToUint64(sizeString);
}
PQclear(result);
ClearResults(connection, raiseInterrupts);
}
return size;
}

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/*-------------------------------------------------------------------------
*
* pgbouncer_manager.h
* Functions for managing outbound pgbouncers
*
* Copyright (c) Citus Data, Inc.
*
*-------------------------------------------------------------------------
*/
#ifndef PGBOUNCER_MANAGER_H
#define PGBOUNCER_MANAGER_H
/* default number of inbound pgbouncer processes (0 is disabled) */
#define PGBOUNCER_INBOUND_PROCS_DEFAULT 0
/* bits reserved for local pgbouncer ID in the pgbouncer peer_id */
#define PGBOUNCER_PEER_ID_LOCAL_ID_BITS 5
/* maximum number of inbound pgbouncer processes */
#define PGBOUNCER_INBOUND_PROCS_MAX ((1 << PGBOUNCER_PEER_ID_LOCAL_ID_BITS) - 1)
/* GUC variable that sets the number of inbound pgbouncer procs */
extern int PgBouncerInboundProcs;
/* GUC variable that sets the inbound pgbouncer port */
extern int PgBouncerInboundPort;
/* GUC variable that sets the path to pgbouncer executable */
extern char *PgBouncerPath;
/* GUC variable that sets a pgbouncer file to include */
extern char *PgBouncerIncludeConfig;
/* global variable to request pgbouncer reconfiguration */
extern bool ReconfigurePgBouncersOnCommit;
void InitializeSharedPgBouncerManager(void);
size_t SharedPgBouncerManagerShmemSize(void);
void PgBouncerManagerMain(Datum arg);
bool PauseDatabaseOnInboundPgBouncers(char *databaseName);
bool ResumeDatabaseOnInboundPgBouncers(char *databaseName);
void TriggerPgBouncerReconfigureIfNeeded(void);
#endif /* PGBOUNCER_MANAGER_H */