simplified-RDBMS-in-python

Implementation of simplified RDBMS in Python, using Lark for parsing and Oracle Berkeley DB. Supports following statements:

• CREATE TABLE
• DROP TABLE
• EXPLAIN/DESCRIBE/DESC
• SHOW TABLES
• INSERT TABLE
• SELECT

Messages

Message Type	Message
SyntaxError	Syntax error
CreateTableSuccess(#tableName)	'#tableName' table is created
DuplicateColumnDefError	Create table has failed: column definition is duplicated
DuplicatePrimaryKeyDefError	Create table has failed: primary key definition is duplicated
ReferenceTypeError	Create table has failed: foreign key references wrong type
ReferenceNonPrimaryKeyError	Create table has failed: foreign key references non primary key column
ReferenceColumnExistenceError	Create table has failed: foreign key references non existing column
ReferenceTableExistenceError	Create table has failed: foreign key references non existing table
NonExistingColumnDefError(#colName)	Create table has failed: '#colName' does not exist in column definition
TableExistenceError	Create table has failed: table with the same name already exists
CharLengthError	Char length should be over 0
DropSuccess(#tableName)	'#tableName' table is dropped
NoSuchTable	No such table
DropReferencedTableError(#tableName)	Drop table has failed: '#tableName' is referenced by other table
SelectTableExistenceError(#tableName)	Selection has failed: '#tableName' does not exist
InsertResult	1 row inserted
InsertTypeMismatchError	Insertion has failed: Types are not matched
InsertColumnExistenceError(#colName)	Insertion has failed: '#colName' does not exist
InsertColumnNonNullableError(#colName)	Insertion has failed: '#colName' is not nullable
DeleteResult(#count)	‘#count’ row(s) deleted
SelectTableExistenceError(#tableName)	Selection has failed: '#tableName' does not exist
SelectColumnResolveError(#colName)	Selection has failed: fail to resolve '#colName'
WhereIncomparableError	Where clause trying to compare incomparable values
WhereTableNotSpecified	Where clause trying to reference tables which are not specified
WhereColumnNotExist	Where clause trying to reference non existing column
WhereAmbiguousReference	Where clause contains ambiguous reference
InsertDuplicatePrimaryKeyError	Insertion has failed: Primary key duplication
InsertReferentialIntegrityError	Insertion has failed: Referential integrity violation
DeleteReferentialIntegrityPassed(#count)	‘#count’ row(s) are not deleted due to referential integrity

Installing Dependencies

macOS

brew install berkeley-db@18
YES_I_HAVE_THE_RIGHT_TO_USE_THIS_BERKELEY_DB_VERSION=1 pip install -r requirements.txt

Linux(Debian)

sudo apt-get install libdb-dev
pip install -r requirements.txt

Running

python3 run.py