/*------------------------------------------------------------------------- * * coordinator_protocol.h * Header for shared declarations for access to coordinator node data. * These data are used to create new shards or update existing ones. * * Copyright (c) Citus Data, Inc. * *------------------------------------------------------------------------- */ #ifndef COORDINATOR_PROTOCOL_H #define COORDINATOR_PROTOCOL_H #include "postgres.h" #include "c.h" #include "fmgr.h" #include "distributed/connection_management.h" #include "distributed/shardinterval_utils.h" #include "nodes/pg_list.h" #include "distributed/metadata_utility.h" /* * In our distributed database, we need a mechanism to make remote procedure * calls between clients, the coordinator node, and worker nodes. These remote calls * require serializing and deserializing values and function signatures between * nodes; and for these, we currently use PostgreSQL's built-in type and * function definition system. This approach is by no means ideal however; and * our implementation: (i) cannot perform compile-time type checks, (ii) * requires additional effort when upgrading to new function signatures, and * (iii) hides argument and return value names and types behind complicated * pg_proc.h definitions. * * An ideal implementation should overcome these problems, and make it much * easier to pass values back and forth between nodes. One such implementation * that comes close to ideal is Google's Protocol Buffers. Nonetheless, we do * not use it in here as its inclusion requires changes to PostgreSQL's make * system, and a native C version is currently unavailable. */ /* Number of tuple fields that coordinator node functions return */ #define TABLE_METADATA_FIELDS 7 #define CANDIDATE_NODE_FIELDS 2 #define WORKER_NODE_FIELDS 2 /* transfer mode for master_copy_shard_placement */ #define TRANSFER_MODE_AUTOMATIC 'a' #define TRANSFER_MODE_FORCE_LOGICAL 'l' #define TRANSFER_MODE_BLOCK_WRITES 'b' /* Name of columnar foreign data wrapper */ #define CSTORE_FDW_NAME "cstore_fdw" #define SHARDID_SEQUENCE_NAME "pg_dist_shardid_seq" #define PLACEMENTID_SEQUENCE_NAME "pg_dist_placement_placementid_seq" /* Remote call definitions to help with data staging and deletion */ #define WORKER_APPLY_SHARD_DDL_COMMAND \ "SELECT worker_apply_shard_ddl_command (" UINT64_FORMAT ", %s, %s)" #define WORKER_APPLY_SHARD_DDL_COMMAND_WITHOUT_SCHEMA \ "SELECT worker_apply_shard_ddl_command (" UINT64_FORMAT ", %s)" #define WORKER_APPEND_TABLE_TO_SHARD \ "SELECT worker_append_table_to_shard (%s, %s, %s, %u)" #define WORKER_APPLY_INTER_SHARD_DDL_COMMAND \ "SELECT worker_apply_inter_shard_ddl_command (" UINT64_FORMAT ", %s, " UINT64_FORMAT \ ", %s, %s)" #define SHARD_RANGE_QUERY "SELECT min(%s), max(%s) FROM %s" #define SHARD_TABLE_SIZE_QUERY "SELECT pg_table_size(%s)" #define SHARD_CSTORE_TABLE_SIZE_QUERY "SELECT cstore_table_size(%s)" #define DROP_REGULAR_TABLE_COMMAND "DROP TABLE IF EXISTS %s CASCADE" #define DROP_FOREIGN_TABLE_COMMAND "DROP FOREIGN TABLE IF EXISTS %s CASCADE" #define CREATE_SCHEMA_COMMAND "CREATE SCHEMA IF NOT EXISTS %s AUTHORIZATION %s" /* Enumeration that defines the shard placement policy to use while staging */ typedef enum { SHARD_PLACEMENT_INVALID_FIRST = 0, SHARD_PLACEMENT_LOCAL_NODE_FIRST = 1, SHARD_PLACEMENT_ROUND_ROBIN = 2, SHARD_PLACEMENT_RANDOM = 3 } ShardPlacementPolicyType; /* Config variables managed via guc.c */ extern int ShardCount; extern int ShardReplicationFactor; extern int ShardMaxSize; extern int ShardPlacementPolicy; extern int NextShardId; extern int NextPlacementId; extern bool IsCoordinator(void); /* Function declarations local to the distributed module */ extern bool CStoreTable(Oid relationId); extern uint64 GetNextShardId(void); extern uint64 GetNextPlacementId(void); extern Oid ResolveRelationId(text *relationName, bool missingOk); extern List * GetFullTableCreationCommands(Oid relationId, bool includeSequenceDefaults); extern List * GetPostLoadTableCreationCommands(Oid relationId); extern List * GetPreLoadTableCreationCommands(Oid relationId, bool includeSequenceDefaults); extern List * GetTableIndexAndConstraintCommands(Oid relationId); extern bool IndexImpliedByAConstraint(Form_pg_index indexForm); extern char ShardStorageType(Oid relationId); extern bool DistributedTableReplicationIsEnabled(void); extern void CheckDistributedTable(Oid relationId); extern void CreateAppendDistributedShardPlacements(Oid relationId, int64 shardId, List *workerNodeList, int replicationFactor); extern void CreateShardsOnWorkers(Oid distributedRelationId, List *shardPlacements, bool useExclusiveConnection, bool colocatedShard); extern List * InsertShardPlacementRows(Oid relationId, int64 shardId, List *workerNodeList, int workerStartIndex, int replicationFactor); extern uint64 UpdateShardStatistics(int64 shardId); extern void CreateShardsWithRoundRobinPolicy(Oid distributedTableId, int32 shardCount, int32 replicationFactor, bool useExclusiveConnections); extern void CreateColocatedShards(Oid targetRelationId, Oid sourceRelationId, bool useExclusiveConnections); extern void CreateReferenceTableShard(Oid distributedTableId); extern List * WorkerCreateShardCommandList(Oid relationId, int shardIndex, uint64 shardId, List *ddlCommandList, List *foreignConstraintCommandList); extern Oid ForeignConstraintGetReferencedTableId(const char *queryString); extern void CheckHashPartitionedTable(Oid distributedTableId); extern void CheckTableSchemaNameForDrop(Oid relationId, char **schemaName, char **tableName); extern text * IntegerToText(int32 value); /* Function declarations for generating metadata for shard and placement creation */ extern Datum master_get_table_metadata(PG_FUNCTION_ARGS); extern Datum master_get_table_ddl_events(PG_FUNCTION_ARGS); extern Datum master_get_new_shardid(PG_FUNCTION_ARGS); extern Datum master_get_new_placementid(PG_FUNCTION_ARGS); extern Datum master_get_active_worker_nodes(PG_FUNCTION_ARGS); extern Datum master_get_round_robin_candidate_nodes(PG_FUNCTION_ARGS); extern Datum master_stage_shard_row(PG_FUNCTION_ARGS); extern Datum master_stage_shard_placement_row(PG_FUNCTION_ARGS); /* Function declarations to help with data staging and deletion */ extern Datum master_create_empty_shard(PG_FUNCTION_ARGS); extern Datum master_append_table_to_shard(PG_FUNCTION_ARGS); extern Datum master_update_shard_statistics(PG_FUNCTION_ARGS); extern Datum master_apply_delete_command(PG_FUNCTION_ARGS); extern Datum master_drop_sequences(PG_FUNCTION_ARGS); extern Datum master_modify_multiple_shards(PG_FUNCTION_ARGS); extern Datum lock_relation_if_exists(PG_FUNCTION_ARGS); extern Datum master_drop_all_shards(PG_FUNCTION_ARGS); extern int MasterDropAllShards(Oid relationId, char *schemaName, char *relationName); /* function declarations for shard creation functionality */ extern Datum master_create_worker_shards(PG_FUNCTION_ARGS); extern Datum isolate_tenant_to_new_shard(PG_FUNCTION_ARGS); /* function declarations for shard repair functionality */ extern Datum master_copy_shard_placement(PG_FUNCTION_ARGS); /* function declarations for shard copy functinality */ extern List * CopyShardCommandList(ShardInterval *shardInterval, const char *sourceNodeName, int32 sourceNodePort, bool includeData); extern List * CopyShardForeignConstraintCommandList(ShardInterval *shardInterval); extern void CopyShardForeignConstraintCommandListGrouped(ShardInterval *shardInterval, List ** colocatedShardForeignConstraintCommandList, List ** referenceTableForeignConstraintList); extern ShardPlacement * SearchShardPlacementInList(List *shardPlacementList, const char *nodeName, uint32 nodePort); extern ShardPlacement * SearchShardPlacementInListOrError(List *shardPlacementList, const char *nodeName, uint32 nodePort); extern char LookupShardTransferMode(Oid shardReplicationModeOid); #endif /* COORDINATOR_PROTOCOL_H */