Package simpledb

Interface Summary

Interface	Description
Aggregator	The common interface for any class that can compute an aggregate over a list of Tuples.
DbFile	The interface for database files on disk.
DbFileIterator	DbFileIterator is the iterator interface that all SimpleDB Dbfile should implement.
DbIterator	DbIterator is the iterator interface that all SimpleDB operators should implement.
Field	Interface for values of fields in tuples in SimpleDB.
Page	Page is the interface used to represent pages that are resident in the BufferPool.
PageId	PageId is an interface to a specific page of a specific table.

Class Summary

Class	Description
Aggregate	The Aggregation operator that computes an aggregate (e.g., sum, avg, max, min).
Aggregator.TupleMapIterator	TupleMapIterator is class which converts HashMap < Field, Tuple > to a DbIterator.
BufferPool	BufferPool manages the reading and writing of pages into memory from disk.
Catalog	The Catalog keeps track of all available tables in the database and their associated schemas.
CostCard	Class returned by JoinOptimizer.computeCostAndCardOfSubplan(java.util.HashMap<java.lang.String, simpledb.TableStats>, java.util.HashMap<java.lang.String, java.lang.Double>, simpledb.LogicalJoinNode, java.util.Set<simpledb.LogicalJoinNode>, double, simpledb.PlanCache) specifying the cost and cardinality of the optimal plan represented by plan.
Database	Database is a class that initializes several static variables used by the database system (the catalog, the buffer pool, and the log files, in particular.)
Debug	Debug is a utility class that wraps println statements and allows more or less command line output to be turned on.
Delete	The delete operator.
Filter	Filter is an operator that implements a relational select.
HashEquiJoin	The Join operator implements the relational join operation.
HeapFile	HeapFile is an implementation of a DbFile that stores a collection of tuples in no particular order.
HeapFileEncoder	HeapFileEncoder reads a comma delimited text file or accepts an array of tuples and converts it to pages of binary data in the appropriate format for simpledb heap pages Pages are padded out to a specified length, and written consecutive in a data file.
HeapPage	Each instance of HeapPage stores data for one page of HeapFiles and implements the Page interface that is used by BufferPool.
HeapPageId	Unique identifier for HeapPage objects.
Insert	Inserts tuples read from the child operator into the tableid specified in the constructor
IntegerAggregator	Knows how to compute some aggregate over a set of IntFields.
IntField	Instance of Field that stores a single integer.
IntHistogram	A class to represent a fixed-width histogram over a single integer-based field.
Join	The Join operator implements the relational join operation.
JoinOptimizer	The JoinOptimizer class is responsible for ordering a series of joins optimally, and for selecting the best instantiation of a join for a given logical plan.
JoinPredicate	JoinPredicate compares fields of two tuples using a predicate.
LockManager	LockManager is class which manages locks for transactions.
LogFile	The format of the log file is as follows: The first long integer of the file represents the offset of the last written checkpoint, or -1 if there are no checkpoints All additional data in the log consists of log records.
LogicalFilterNode	A LogicalFilterNode represents the parameters of a filter in the WHERE clause of a query.
LogicalJoinNode	A LogicalJoinNode represens the state needed of a join of two tables in a LogicalQueryPlan
LogicalPlan	LogicalPlan represents a logical query plan that has been through the parser and is ready to be processed by the optimizer.
LogicalScanNode	A LogicalScanNode represents table in the FROM list in a LogicalQueryPlan
LogicalSelectListNode	A LogicalSelectListNode represents a clause in the select list in a LogicalQueryPlan
LogicalSubplanJoinNode	A LogicalSubplanJoinNode represens the state needed of a join of a table to a subplan in a LogicalQueryPlan -- inherits state from LogicalJoinNode; t2 and f2 should always be null
LRUCache<K,V>	Last Recently used policy cache.
Operator	Abstract class for implementing operators.
OperatorCardinality	A utility class, which computes the estimated cardinalities of an operator tree.
OrderBy	OrderBy is an operator that implements a relational ORDER BY.
Parser
Permissions	Class representing requested permissions to a relation/file.
PlanCache	A PlanCache is a helper class that can be used to store the best way to order a given set of joins
Predicate	Predicate compares tuples to a specified Field value.
Project	Project is an operator that implements a relational projection.
Project1Test
Project2Test
Query	Query is a wrapper class to manage the execution of queries.
QueryPlanVisualizer
QueryPlanVisualizer.SubTreeDescriptor
RecordId	A RecordId is a reference to a specific tuple on a specific page of a specific table.
SeqScan	SeqScan is an implementation of a sequential scan access method that reads each tuple of a table in no particular order (e.g., as they are laid out on disk).
SimpleDb
StringAggregator	Knows how to compute some aggregate over a set of StringFields.
StringField	Instance of Field that stores a single String of a fixed length.
StringHistogram	A class to represent a fixed-width histogram over a single String-based field.
TableStats	TableStats represents statistics (e.g., histograms) about base tables in a query.
Transaction	Transaction encapsulates information about the state of a transaction and manages transaction commit / abort.
TransactionId	TransactionId is a class that contains the identifier of a transaction.
Tuple	Tuple maintains information about the contents of a tuple.
TupleArrayIterator
TupleComparator
TupleDesc	TupleDesc describes the schema of a tuple.
TupleDesc.TDItem	A help class to facilitate organizing the information of each field
TupleIterator	Implements a DbIterator by wrapping an Iterable < Tuple >.
Utility	Helper methods used for testing and implementing random features.

Enum Summary

Enum	Description
Aggregator.Op
Predicate.Op	Constants used for return codes in Field.compare
Type	Class representing a type in SimpleDB.

Exception Summary

Exception	Description
DbException	Generic database exception class
ParsingException
TransactionAbortedException	Exception that is thrown when a transaction has aborted.