Return the catalog of the static Database instance

Returns the next tuple from the operator (typically implementing by reading from a child operator or an access method). @return the next tuple in the

@return a Tuple with a single IntField with value n and with RecordId(HeapPageId(1,2), 3)

Return the id of this page. The id is a unique identifier for a page that can be used to look up the page on disk or determine if the page is residen

Returns true if the iterator has more tuples. @return true f the iterator has more tuples. @throws IllegalStateException If the iterator has not been

Opens the iterator. This must be called before any of the other methods. @throws DbException when there are problems opening/accessing the database.

Set up initial resources for each unit test.

Returns the TupleDesc of the table stored in this DbFile. @return TupleDesc of this DbFile.

@return a TupleDesc with n fields of type Type.INT_TYPE, each named name + n (name1, name2, etc.).

@return the value of the ith field, or null if it has not been set. @param i field index to return. Must be a valid index.

@param columnSpecification Mapping between column index and value.

Returns an ID uniquely identifying this HeapFile. Implementation note: you will need to generate this tableid somewhere ensure that each HeapFile has

Add a value to the set of values that you are keeping a histogram of. @param v Value to add to the histogram

Closes the iterator. When the iterator is closed, calling next(), hasNext(), or rewind() should fail by throwing IllegalStateException.

Return the buffer pool of the static Database instance

Change the value of the ith field of this tuple. @param i index of the field to change. It must be a valid index. @param f new value for the field.

Estimate the selectivity of predicate <tt>field op constant</tt> on the table. @param field The field over which the predicate ranges @param op The l

Estimate the selectivity of a particular predicate and operand on this table. For example, if "op" is "GREATER_THAN" and "v" is 5, return your estima

Returns an iterator over all the tuples stored in this DbFile. The iterator must use {@link BufferPool#getPage}, rather than {@link #readPage} to iter

Retrieve the specified page with the associated permissions. Will acquire a lock and may block if that lock is held by another transaction. <p> The re

@return the unique tableid hashcode with this PageId

@return the number of fields in this TupleDesc

Helper method to clean up the syntax of starting a LockGrabber thread. The parameters pass through to the LockGrabber constructor.

Release all locks associated with a given transaction. @param tid the ID of the transaction requesting the unlock

@return a DbIterator over a list of tuples constructed over the data provided in the constructor. This iterator is already open. @param width the nu

Hash code. Different Field objects representing the same value should probably return the same hashCode.

@return true if we successfully acquired the specified lock

Compares the field number of t specified in the constructor to the operand field specified in the constructor using the operator specific in the const

Given a matrix of tuples from SystemTestUtil.createRandomHeapFile, create an identical HeapFile table @param tuples Tuples to create a HeapFile from @

@return an IntField with value n

Find the index of the field with a given name. @param name name of the field. @return the index of the field that is first to have the given name. @t

Given a name of a field, try to figure out what table it belongs to by looking through all of the tables added via {@link #addScan}. @return A full

Apply the predicate to the two specified tuples. The comparison can be made through Field's compare method. @return true if the tuples satisfy the pre

Returns the type of this field (see {@link Type#INT_TYPE} or {@link Type#STRING_TYPE} @return type of this field

Check to see if every tuple in expected matches <b>some</b> tuple in actual via compareTuples. Note that actual may be a superset. If not, throw an

This method returns the number of tuples in the relation, given that a predicate with selectivity selectivityFactor is applied. @param selectivityFac

Gets the (possibly null) field name of the ith field of this TupleDesc. @param i index of the field name to return. It must be a valid index. @return

Resets the iterator to the start. @throws DbException when rewind is unsupported. @throws IllegalStateException If the iterator has not been opened

Gets the type of the ith field of this TupleDesc. @param i The index of the field to get the type of. It must be a valid index. @return the type of t

Log message if the log level >= level. Uses printf.

Method used for testing -- create a new instance of the buffer pool and return it

Compares one PageId to another. @param o The object to compare against (must be a PageId) @return true if the objects are equal (e.g., page numbers a

Compares the specified object with this TupleDesc for equality. Two TupleDescs are considered equal if they are the same size and if the n-th type in

@return The size (in bytes) of tuples corresponding to this TupleDesc. Note that tuples from a given TupleDesc are of a fixed size.

Set the dirty state of this page as dirtied by a particular transaction

Unit test for TupleDesc.numFields()

@return true iff the tuples have the same number of fields and corresponding fields in the two Tuples are all equal.

Returns the DbFile that can be used to read the contents of the specified table. @param tableid The id of the table, as specified by the DbFile.getId(

@return The RecordId representing the location of this tuple on disk. May be null.

Returns true if associated slot on this page is filled.

Returns the TupleDesc associated with this DbIterator. @return the TupleDesc associated with this DbIterator.

Generic unit test structure for BufferPool.getPage() assuming locking. @param tid1 the first transaction Id @param pid1 the first page to lock over @

Set the RecordId information for this tuple. @param rid the new RecordId for this tuple.

Checks if the sequence represents an arithmetic sequence (approximately) ret[0] is true if the sequence is linear ret[1] is the common difference of t

Returns the number of empty slots on this page.

Returns the next tuple, or throws NoSuchElementException if the iterator is closed. @return The next tuple in the iterator @th

Opens a HeapFile and adds it to the catalog. @param cols number of columns in the table. @param f location of the file storing the table. @return the

Close the iterator

Estimates the cost of sequentially scanning the file, given that the cost to read a page is costPerPageIO. You can assume that there are no seeks and

@return an Exception instance if one occured during lock acquisition; null otherwise

@return The TupleDesc representing the schema of this tuple.

Gets the next tuple from the operator (typically implementing by reading from a child operator or an access method). @return The next tuple in the it

Adds the specified tuple to the file on behalf of transaction. This method will acquire a lock on the affected pages of the file, and may block until

Compare the value of this field object to the passed in value. @param op The operator @param value The value to compare this Field to @return Whether

Convert the specified tuple list (with only integer fields) into a binary page file. <br> The format of the output file will be as specified in HeapP

Flush all dirty pages to disk. NB: Be careful using this routine -- it writes dirty data to disk so will break simpledb if running in NO STEAL mode.

Generates a unique string each time it is called. @return a new unique UUID as a string, using java.util.UUID

@return true if there are more tuples available.

Return true if field is a primary key of the specified table, false otherwise

Opens the iterator @throws DbException when there are problems opening/accessing the database.

Adds the specified tuple to the page; the tuple should be updated to reflect that it is now stored on this page. @throws DbException if the page is

Verifies that the DbIterator has been exhausted of all elements.

Closes the iterator.

Merge two TupleDescs into one, with td1.numFields + td2.numFields fields, with the first td1.numFields coming from td1 and the remaining from td2. @pa

Delete the specified tuple from the page; the tuple should be updated to reflect that it is no longer stored on any page. @throws DbException if th

@return true if there are more tuples remaining.

Create a DbIterator over group aggregate results. @return a DbIterator whose tuples are the pair (groupVal, aggregateVal) if using group, or a sing

Marks this page as dirty/not dirty and record that transaction that did the dirtying

Merge a new tuple into the aggregate, grouping as indicated in the constructor @param tup the Tuple containing an aggregate field and a group-by field

Returns the number of pages in this HeapFile.

Start the transaction running