Assignment 3 - Record Manager

TEAM MEMBERS (GROUP 3)

Vivekanand Reddy Malipatel - A20524971
Indrajit Ghosh - A20525793
Sai Ram Oduri - A20522183

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Note ---->
The test_assign3_1.c has been modified to satisfy the Primary Key implementation and the initial memory leak.

Optional Functions Implemented ----->

1. TID and Tombstone : We are using + and - Symbols for tombstone functionality while inserting and deleting the records.
2. Primary Key : checkPrimaryKey() Functions retirves all the records in the table and checks for the primary key violation and trhows RC_PRIMARYKEY_VIOLATION, if found.

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Description----->

The record manager handles tables with a fixed schema. Clients can insert records, delete records, update records, and scan through the records in a table. 
A scan is associated with a search condition and only returns records that match the search condition. 
Each table should be stored in a separate page file and your record manager should access the pages of the file through the buffer manager implemented in the last assignment.

Script Execution---->

1. Go to the terminal inside the project folder
2. use "make clean" to clear the auto generated files.
3. use "make" command to compile the file
4. use "make run" to run the test case test_assign3_1.c
5. use "make run1" to run the test case test_expr.c
5. use Step - 2 again before running the another testcase.

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Implemented by Indrajit Ghosh

Function Implementations -

initRecordManager()--> This function is used to initialize the recordmanager which internally calls the storage manager.

shutdownRecordManager()--> This function is used to shut down the Record Manager and free all the memory used by it.

createTable()-->  This function creates a table , with the name, schema given as argument. It checks whether the schema is too big in size or 
the record size is too big for a reference page size.

openTable()-->This function opens a table with the given name and sets its metadata to a custom record Manager metadata.

closeTable()-->This function is used to close the opened table, shutdown the bufferpool and set the table metadata to Null

deleteTable()--> This method will be used to delete the page file from the disk associated with the table name.

getNumTuples()--> This method will be used to get the number of tuples in the table whose content can be found using the metadata.

Test case for Primary keys - testPrimaryKey()-->This function has been implemented in test_assign3_1.c, which validates that the primary key logic , which
get activate only when activatePkeyTag() is called.
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Implemented by Vivekanand Reddy Malipatel

Function Implementations -

checkPrimaryKey() ----> This function checks the primary key functionality.

insertRecord() ---> This function is used to insert tuples to the table from the record. It Initially finds for the free page and copies the records into the table using memcpy() method.

deleteRecord() ----> This function deletes the tuples from the table.

updateRecord() -----> This function updates the tuples from the table.

getRecord() -------> Thsi function retrieves the record with the given RID.

startScan() --------> This Function Initialises the Scan manager with the given TableData, Scan conditiona and Handler.

next() ---> This Function scans the tuples in the table with the given scan condition and return "RC_RM_NO_MORE_TUPLES" if it reaches end of the table.

closeScan() -----> This function closes the scan manager and free the Scanmanager memory.

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Implemented by Sai Ram Oduri

Function Implementations -

getRecordSize()---> GetRecordSize function calculates the actual size of the schema on the disk by taking each bytes' size and adding them up

createSchema()---> to create a new schema build a blueprint of the schema, including the attributes required.This function helps to build a new schema.

freeSchema()--->  Free Schema is to delete Schema and the variables completely with all the memory it has occupied
createRecord()---> Build a record in the schema, referring to "schema"
bytes_offsetting()--->This function is taken from the Record manager serializer , to calculate position of the pointer from the previously passed location.
This will set the attributes on the disk in a serial fashion

freeRecord()--->We need to freeRecord from the memory.
getAttr()---> Get Attr function takes,Record with all the data,Schema with all the data in the schema,Attribute Numbers to retrieve the attributes in the schema
Value of the expression.

setAttr()--->Set Attr function takes,Record with all the data,Schema with all the data in the schema,Attribute Numbers to set the attributes in the schema
Value of the expression.