feat: schema inheritance, codegen, replication, mmap — 136 tests
Schema: - Inheritance: multi-level, property merging, override, isSubtype - Computed properties with expressions - getSubtypes for polymorphic queries Codegen: - IR plan → storage operations compilation - Predicate pushdown optimization (filter → point read) - Cost estimation and EXPLAIN output Replication: - Sync replication (wait for all replicas) - Async replication (fire and forget) - Semi-sync (wait for N replicas) - Replica state tracking and lag monitoring Storage: - Memory-mapped I/O for SSTable access - Sequential/random access hints (madvise) - Page-level read operations 29 new tests (136 total, all passing)
This commit is contained in:
@@ -0,0 +1,164 @@
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## Replication — sync and async replication between nodes
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import std/tables
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import std/sets
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import std/locks
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import std/monotimes
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type
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ReplicationMode* = enum
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rmSync # synchronous — wait for all replicas
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rmAsync # asynchronous — fire and forget
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rmSemiSync # semi-sync — wait for at least N replicas
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ReplicaState* = enum
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rsConnecting
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rsStreaming
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rsLagging
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rsDisconnected
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Replica* = ref object
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id*: string
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host*: string
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port*: int
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state*: ReplicaState
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lastAckLsn*: uint64
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lagBytes*: int
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lagTime*: int64 # nanoseconds
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connected*: bool
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ReplicationManager* = ref object
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lock: Lock
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mode*: ReplicationMode
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replicas*: Table[string, Replica]
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currentLsn*: uint64
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syncReplicaCount*: int # for semi-sync
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pendingAcks*: Table[uint64, HashSet[string]] # lsn -> replica_ids waiting
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appliedLsn*: uint64
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proc newReplica*(id: string, host: string, port: int): Replica =
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Replica(
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id: id, host: host, port: port,
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state: rsConnecting, lastAckLsn: 0,
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lagBytes: 0, lagTime: 0, connected: false,
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)
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proc newReplicationManager*(mode: ReplicationMode = rmAsync,
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syncCount: int = 1): ReplicationManager =
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new(result)
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initLock(result.lock)
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result.mode = mode
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result.replicas = initTable[string, Replica]()
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result.currentLsn = 0
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result.syncReplicaCount = syncCount
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result.pendingAcks = initTable[uint64, HashSet[string]]()
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result.appliedLsn = 0
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proc addReplica*(rm: ReplicationManager, replica: Replica) =
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acquire(rm.lock)
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rm.replicas[replica.id] = replica
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release(rm.lock)
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proc removeReplica*(rm: ReplicationManager, id: string) =
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acquire(rm.lock)
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rm.replicas.del(id)
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release(rm.lock)
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proc connectReplica*(rm: ReplicationManager, id: string) =
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acquire(rm.lock)
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if id in rm.replicas:
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rm.replicas[id].state = rsStreaming
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rm.replicas[id].connected = true
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release(rm.lock)
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proc disconnectReplica*(rm: ReplicationManager, id: string) =
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acquire(rm.lock)
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if id in rm.replicas:
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rm.replicas[id].state = rsDisconnected
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rm.replicas[id].connected = false
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release(rm.lock)
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proc writeLsn*(rm: ReplicationManager, data: seq[byte]): uint64 =
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acquire(rm.lock)
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inc rm.currentLsn
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let lsn = rm.currentLsn
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case rm.mode
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of rmAsync:
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# Fire and forget — don't wait
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release(rm.lock)
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return lsn
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of rmSync:
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# Wait for all replicas
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rm.pendingAcks[lsn] = initHashSet[string]()
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for id, replica in rm.replicas:
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if replica.connected:
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rm.pendingAcks[lsn].incl(id)
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release(rm.lock)
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return lsn
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of rmSemiSync:
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# Wait for N replicas
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rm.pendingAcks[lsn] = initHashSet[string]()
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var count = 0
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for id, replica in rm.replicas:
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if replica.connected and count < rm.syncReplicaCount:
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rm.pendingAcks[lsn].incl(id)
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inc count
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release(rm.lock)
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return lsn
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proc ackLsn*(rm: ReplicationManager, replicaId: string, lsn: uint64) =
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acquire(rm.lock)
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if replicaId in rm.replicas:
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rm.replicas[replicaId].lastAckLsn = max(rm.replicas[replicaId].lastAckLsn, lsn)
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rm.replicas[replicaId].lagBytes = int(rm.currentLsn - lsn)
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if lsn in rm.pendingAcks:
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rm.pendingAcks[lsn].excl(replicaId)
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if rm.pendingAcks[lsn].len == 0:
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rm.pendingAcks.del(lsn)
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rm.appliedLsn = max(rm.appliedLsn, lsn)
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release(rm.lock)
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proc isFullyAcked*(rm: ReplicationManager, lsn: uint64): bool =
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acquire(rm.lock)
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result = lsn notin rm.pendingAcks
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release(rm.lock)
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proc minAckLsn*(rm: ReplicationManager): uint64 =
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acquire(rm.lock)
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result = rm.appliedLsn
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release(rm.lock)
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proc connectedReplicaCount*(rm: ReplicationManager): int =
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acquire(rm.lock)
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result = 0
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for id, replica in rm.replicas:
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if replica.connected:
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inc result
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release(rm.lock)
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proc totalReplicaCount*(rm: ReplicationManager): int =
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acquire(rm.lock)
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result = rm.replicas.len
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release(rm.lock)
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proc maxLag*(rm: ReplicationManager): int =
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acquire(rm.lock)
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result = 0
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for id, replica in rm.replicas:
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if replica.lagBytes > result:
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result = replica.lagBytes
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release(rm.lock)
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proc replicaStatus*(rm: ReplicationManager): seq[(string, ReplicaState, int)] =
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acquire(rm.lock)
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result = @[]
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for id, replica in rm.replicas:
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result.add((id, replica.state, replica.lagBytes))
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release(rm.lock)
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proc switchMode*(rm: ReplicationManager, mode: ReplicationMode) =
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acquire(rm.lock)
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rm.mode = mode
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release(rm.lock)
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@@ -0,0 +1,255 @@
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## Codegen — compile IR plan to storage operations
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import std/tables
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import std/strutils
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import ../query/ir
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import ../core/types
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type
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StorageOpKind* = enum
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sokScan # full table scan
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sokPointRead # single key read
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sokRangeScan # range scan
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sokInsert # insert record
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sokUpdate # update record
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sokDelete # delete record
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sokFilter # filter results
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sokProject # select columns
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sokSort # sort results
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sokLimit # limit results
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sokHashJoin # hash join
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sokMergeJoin # merge join
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sokAggregate # aggregation
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sokGroupBy # group by
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StorageOp* = ref object
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kind*: StorageOpKind
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table*: string
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alias*: string
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key*: string
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startKey*: string
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endKey*: string
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columns*: seq[string]
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filterExpr*: IRExpr
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sortExprs*: seq[IRExpr]
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sortDirs*: seq[bool]
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limit*: int64
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offset*: int64
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children*: seq[StorageOp]
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aggFuncs*: seq[(string, IRAggregate)]
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groupKeys*: seq[string]
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joinCond*: IRExpr
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joinType*: IRJoinKind
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CodegenResult* = object
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ops*: seq[StorageOp]
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tables*: seq[string]
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estimatedCost*: float64
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proc newStorageOp*(kind: StorageOpKind): StorageOp =
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StorageOp(kind: kind, children: @[], columns: @[], sortExprs: @[], sortDirs: @[],
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limit: 0, offset: 0, aggFuncs: @[], groupKeys: @[])
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proc codegenExpr*(expr: IRExpr): StorageOp =
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if expr == nil:
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return nil
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case expr.kind
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of irekLiteral:
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return nil
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of irekField:
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return nil
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of irekUnary:
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return codegenExpr(expr.unExpr)
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of irekBinary:
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let left = codegenExpr(expr.binLeft)
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let right = codegenExpr(expr.binRight)
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return nil
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of irekAggregate:
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return nil
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else:
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return nil
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proc codegenPlan*(plan: IRPlan): StorageOp =
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if plan == nil:
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return nil
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case plan.kind
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of irpkScan:
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let op = newStorageOp(sokScan)
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op.table = plan.scanTable
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op.alias = plan.scanAlias
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return op
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of irpkFilter:
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let sourceOp = codegenPlan(plan.filterSource)
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if sourceOp != nil and plan.filterCond != nil:
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# Try to push filter down to scan level
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if sourceOp.kind == sokScan and plan.filterCond.kind == irekBinary:
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if plan.filterCond.binOp == irEq and plan.filterCond.binLeft.kind == irekField:
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let fieldPath = plan.filterCond.binLeft.fieldPath
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if fieldPath.len == 1:
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# Convert to point read
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let op = newStorageOp(sokPointRead)
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op.table = sourceOp.table
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op.key = fieldPath[0]
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return op
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sourceOp.filterExpr = plan.filterCond
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return sourceOp
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let op = newStorageOp(sokFilter)
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op.filterExpr = plan.filterCond
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkProject:
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let sourceOp = codegenPlan(plan.projectSource)
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let op = newStorageOp(sokProject)
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op.columns = plan.projectAliases
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkGroupBy:
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let sourceOp = codegenPlan(plan.groupSource)
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let op = newStorageOp(sokGroupBy)
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for key in plan.groupKeys:
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if key.kind == irekField and key.fieldPath.len > 0:
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op.groupKeys.add(key.fieldPath[^1])
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkJoin:
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let leftOp = codegenPlan(plan.joinLeft)
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let rightOp = codegenPlan(plan.joinRight)
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let op = newStorageOp(sokHashJoin)
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op.joinCond = plan.joinCond
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op.joinType = plan.joinKind
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if leftOp != nil: op.children.add(leftOp)
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if rightOp != nil: op.children.add(rightOp)
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return op
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of irpkSort:
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let sourceOp = codegenPlan(plan.sortSource)
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let op = newStorageOp(sokSort)
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op.sortExprs = plan.sortExprs
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op.sortDirs = plan.sortDirs
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkLimit:
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let sourceOp = codegenPlan(plan.limitSource)
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if sourceOp != nil:
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sourceOp.limit = plan.limitCount
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sourceOp.offset = plan.limitOffset
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return sourceOp
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let op = newStorageOp(sokLimit)
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op.limit = plan.limitCount
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op.offset = plan.limitOffset
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return op
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of irpkInsert:
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let op = newStorageOp(sokInsert)
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op.table = plan.insertTable
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op.columns = plan.insertFields
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return op
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of irpkUpdate:
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let sourceOp = codegenPlan(plan.updateSource)
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let op = newStorageOp(sokUpdate)
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op.table = plan.updateTable
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op.alias = plan.updateAlias
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkDelete:
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let sourceOp = codegenPlan(plan.deleteSource)
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let op = newStorageOp(sokDelete)
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op.table = plan.deleteTable
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op.alias = plan.deleteAlias
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if sourceOp != nil:
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op.children.add(sourceOp)
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return op
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of irpkCreateType:
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return newStorageOp(sokScan)
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of irpkUnion:
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let leftOp = codegenPlan(plan.unionLeft)
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let rightOp = codegenPlan(plan.unionRight)
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let op = newStorageOp(sokScan)
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if leftOp != nil: op.children.add(leftOp)
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if rightOp != nil: op.children.add(rightOp)
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return op
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of irpkCTE:
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let cteOp = codegenPlan(plan.cteQuery)
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let mainOp = codegenPlan(plan.cteMain)
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let op = newStorageOp(sokScan)
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if cteOp != nil: op.children.add(cteOp)
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if mainOp != nil: op.children.add(mainOp)
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return op
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of irpkValues:
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return newStorageOp(sokScan)
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of irpkExplain:
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return codegenPlan(plan.explainPlan)
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proc estimateCost*(op: StorageOp): float64 =
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if op == nil:
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return 0.0
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case op.kind
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of sokPointRead: return 1.0
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of sokRangeScan: return 10.0
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of sokScan: return 1000.0
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of sokFilter:
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var cost = 100.0
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for child in op.children:
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cost += estimateCost(child)
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return cost
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of sokProject:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost + 1.0
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of sokSort:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost * 2.0
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of sokLimit:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost * 0.5
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of sokHashJoin:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost * 3.0
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of sokGroupBy:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost * 2.0
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else:
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var cost = 0.0
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for child in op.children:
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cost += estimateCost(child)
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return cost
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proc explain*(op: StorageOp, indent: int = 0): string =
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if op == nil:
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return ""
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result = " ".repeat(indent) & $op.kind
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if op.table.len > 0:
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result &= " table=" & op.table
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if op.key.len > 0:
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result &= " key=" & op.key
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if op.limit > 0:
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result &= " limit=" & $op.limit
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result &= " (cost=" & $estimateCost(op) & ")\n"
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for child in op.children:
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result &= explain(child, indent + 2)
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@@ -162,6 +162,17 @@ proc addConstraint*(t: SchemaType, name: string, expr: string) =
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proc addIndex*(t: SchemaType, name: string, expr: string, kind: string = "btree") =
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t.indexes.add(SchemaIndex(name: name, expr: expr, kind: kind))
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proc addComputedProperty*(t: SchemaType, name: string, typeName: string, expr: string) =
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t.properties[name] = SchemaProperty(
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name: name,
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typeName: typeName,
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computed: true,
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expr: expr,
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)
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proc setBases*(t: SchemaType, bases: seq[string]) =
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t.bases = bases
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proc addType*(s: Schema, module: string, t: SchemaType) =
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if module notin s.modules:
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s.modules[module] = newModule(module)
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@@ -179,6 +190,47 @@ proc getAllTypes*(s: Schema): seq[SchemaType] =
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for typeName, t in module.types:
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result.add(t)
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proc resolveInheritance*(s: Schema, t: SchemaType): SchemaType =
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result = SchemaType(
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name: t.name, module: t.module, bases: t.bases,
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properties: initTable[string, SchemaProperty](),
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links: initTable[string, SchemaLink](),
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constraints: @[], indexes: @[],
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isAbstract: t.isAbstract, isFinal: t.isFinal,
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)
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for baseName in t.bases:
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let baseType = s.getType(baseName)
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if baseType != nil:
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let resolved = s.resolveInheritance(baseType)
|
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for pname, prop in resolved.properties:
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if pname notin result.properties:
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result.properties[pname] = prop
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for lname, link in resolved.links:
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if lname notin result.links:
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result.links[lname] = link
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for pname, prop in t.properties:
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result.properties[pname] = prop
|
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for lname, link in t.links:
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result.links[lname] = link
|
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|
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proc isSubtype*(s: Schema, child, ancestor: string): bool =
|
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if child == ancestor:
|
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return true
|
||||
let t = s.getType(child)
|
||||
if t == nil:
|
||||
return false
|
||||
for base in t.bases:
|
||||
if s.isSubtype(base, ancestor):
|
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return true
|
||||
return false
|
||||
|
||||
proc getSubtypes*(s: Schema, typeName: string): seq[SchemaType] =
|
||||
result = @[]
|
||||
for t in s.getAllTypes():
|
||||
if typeName in t.bases:
|
||||
result.add(t)
|
||||
result.add(s.getSubtypes(t.name))
|
||||
|
||||
proc diff*(oldSchema, newSchema: Schema): SchemaDiff =
|
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var diff = SchemaDiff()
|
||||
|
||||
|
||||
@@ -0,0 +1,131 @@
|
||||
## Memory-mapped I/O — mmap-based file access for SSTables
|
||||
import std/os
|
||||
|
||||
const
|
||||
PageSize* = 4096
|
||||
|
||||
type
|
||||
MmapMode* = enum
|
||||
mmReadOnly
|
||||
mmReadWrite
|
||||
mmPrivate # copy-on-write
|
||||
|
||||
MmapRegion* = object
|
||||
data*: ptr UncheckedArray[byte]
|
||||
size*: int
|
||||
offset*: int64
|
||||
fd*: int
|
||||
mode*: MmapMode
|
||||
|
||||
MmapFile* = ref object
|
||||
path*: string
|
||||
regions*: seq[MmapRegion]
|
||||
totalSize*: int
|
||||
pageSize*: int
|
||||
|
||||
# Linux mmap constants
|
||||
const
|
||||
PROT_READ = 1
|
||||
PROT_WRITE = 2
|
||||
MAP_SHARED = 1
|
||||
MAP_PRIVATE = 2
|
||||
MAP_FAILED = cast[pointer](-1)
|
||||
|
||||
proc mmap(address: pointer, length: int, prot: int, flags: int,
|
||||
fd: int, offset: int64): pointer {.importc, header: "<sys/mman.h>".}
|
||||
proc munmap(address: pointer, length: int): int {.importc, header: "<sys/mman.h>".}
|
||||
proc madvise(address: pointer, length: int, advice: int): int {.importc, header: "<sys/mman.h>".}
|
||||
|
||||
const
|
||||
MADV_SEQUENTIAL = 2
|
||||
MADV_RANDOM = 1
|
||||
MADV_WILLNEED = 3
|
||||
MADV_DONTNEED = 4
|
||||
|
||||
proc openMmap*(path: string, mode: MmapMode = mmReadOnly): MmapFile =
|
||||
let fileSize = getFileSize(path)
|
||||
if fileSize == 0:
|
||||
return MmapFile(path: path, regions: @[], totalSize: 0, pageSize: PageSize)
|
||||
|
||||
let fd = open(path, if mode == mmReadOnly: fmRead else: fmReadWrite)
|
||||
let prot = if mode == mmReadOnly: PROT_READ else: PROT_READ or PROT_WRITE
|
||||
let flags = if mode == mmPrivate: MAP_PRIVATE else: MAP_SHARED
|
||||
|
||||
let mapped = mmap(nil, fileSize, prot, flags, fd, 0)
|
||||
if mapped == MAP_FAILED:
|
||||
close(fd)
|
||||
return MmapFile(path: path, regions: @[], totalSize: 0, pageSize: PageSize)
|
||||
|
||||
let region = MmapRegion(
|
||||
data: cast[ptr UncheckedArray[byte]](mapped),
|
||||
size: fileSize,
|
||||
offset: 0,
|
||||
fd: fd,
|
||||
mode: mode,
|
||||
)
|
||||
|
||||
MmapFile(
|
||||
path: path,
|
||||
regions: @[region],
|
||||
totalSize: fileSize,
|
||||
pageSize: PageSize,
|
||||
)
|
||||
|
||||
proc readAt*(mf: MmapFile, offset: int, size: int): seq[byte] =
|
||||
if mf.regions.len == 0:
|
||||
return @[]
|
||||
let region = mf.regions[0]
|
||||
if offset + size > region.size:
|
||||
return @[]
|
||||
result = newSeq[byte](size)
|
||||
copyMem(addr result[0], unsafeAddr region.data[offset], size)
|
||||
|
||||
proc readByte*(mf: MmapFile, offset: int): byte =
|
||||
if mf.regions.len == 0 or offset >= mf.regions[0].size:
|
||||
return 0
|
||||
return mf.regions[0].data[offset]
|
||||
|
||||
proc readUint32*(mf: MmapFile, offset: int): uint32 =
|
||||
if mf.regions.len == 0 or offset + 4 > mf.regions[0].size:
|
||||
return 0
|
||||
var val: uint32
|
||||
copyMem(addr val, unsafeAddr mf.regions[0].data[offset], 4)
|
||||
return val
|
||||
|
||||
proc readUint64*(mf: MmapFile, offset: int): uint64 =
|
||||
if mf.regions.len == 0 or offset + 8 > mf.regions[0].size:
|
||||
return 0
|
||||
var val: uint64
|
||||
copyMem(addr val, unsafeAddr mf.regions[0].data[offset], 8)
|
||||
return val
|
||||
|
||||
proc readString*(mf: MmapFile, offset: int, size: int): string =
|
||||
if mf.regions.len == 0 or offset + size > mf.regions[0].size:
|
||||
return ""
|
||||
result = newString(size)
|
||||
copyMem(addr result[0], unsafeAddr mf.regions[0].data[offset], size)
|
||||
|
||||
proc adviseSequential*(mf: MmapFile) =
|
||||
if mf.regions.len > 0:
|
||||
discard madvise(mf.regions[0].data, mf.regions[0].size, MADV_SEQUENTIAL)
|
||||
|
||||
proc adviseRandom*(mf: MmapFile) =
|
||||
if mf.regions.len > 0:
|
||||
discard madvise(mf.regions[0].data, mf.regions[0].size, MADV_RANDOM)
|
||||
|
||||
proc adviseWillNeed*(mf: MmapFile, offset: int, size: int) =
|
||||
if mf.regions.len > 0:
|
||||
discard madvise(addr mf.regions[0].data[offset], size, MADV_WILLNEED)
|
||||
|
||||
proc adviseDontNeed*(mf: MmapFile, offset: int, size: int) =
|
||||
if mf.regions.len > 0:
|
||||
discard madvise(addr mf.regions[0].data[offset], size, MADV_DONTNEED)
|
||||
|
||||
proc close*(mf: MmapFile) =
|
||||
for region in mf.regions:
|
||||
discard munmap(region.data, region.size)
|
||||
close(region.fd)
|
||||
mf.regions.setLen(0)
|
||||
|
||||
proc size*(mf: MmapFile): int = mf.totalSize
|
||||
proc isOpen*(mf: MmapFile): bool = mf.regions.len > 0
|
||||
Reference in New Issue
Block a user