def loadData(self):
self._typeCheckerList = []
self.openFile()
for db in self._dataFile:
self._typeCheckerList.append(Database(db['_name']))
database = self.searchDatabase(db['_name'])
for tb in db['_tables']:
table = Table(tb['_name'])
database.tables.append(table)
for col in tb['_colums']:
column = Column(col['_name'], col['_dataType'])
column.number = col['_number']
column.length = col['_length']
column.default = col['_default']
column.notNull = col['_notNull']
column.unique = col['_unique']
column.constraint = col['_constraint']
column.check = col['_check']
column.primaryKey = col['_primaryKey']
# column.autoincrement = col['_autoincrement']
# TODO FOREIGN KEY implementation column.foreignKey = col['_foreignKey']
table.columns.append(column)
def createColumnTable(self, table: Table, column: Column, noLine,
noColumn):
"""
Method to create a column in table
:param table: The name of table
:param column: Number of columns
:param noLine: The instruction line
:param noColumn: The instruction column
:return: Returns nothing
"""
database = SymbolTable().useDatabase
if not database:
desc = f": Database not selected"
ErrorController().add(4, 'Execution', desc, noLine, noColumn)
return
if self.searchColumn(table, column.name):
desc = f": Column {column.name} already exists"
ErrorController().add(29, 'Execution', desc, noLine, noColumn)
return
dbStatement = data_mode.mode(database.mode).alterAddColumn(
database.name.lower(), table.name.lower(), column.default)
if dbStatement == 0:
if len(table.columns) > 0:
column.number = table.columns[-1].number + 1
table.columns.append(column)
self.writeFile()
DataWindow().consoleText(
'Query returned successfully: Table updated')
return True
elif dbStatement == 1:
desc = f": Can't update table {table.name}"
ErrorController().add(34, 'Execution', desc, noLine, noColumn)
elif dbStatement == 2:
desc = f": Database {database.name} does not exist"
ErrorController().add(35, 'Execution', desc, noLine, noColumn)
elif dbStatement == 3:
desc = f": Table {table.name} does not exist"
ErrorController().add(27, 'Execution', desc, noLine, noColumn)
def createColumnTable(self, database: Database, table: Table,
column: Column, noLine, noColumn):
"""
Method to create a column in table
:param database: Table database
:param table: The name of table
:param column: Number of columns
:param noLine: The instruction line
:param noColumn: The instruction column
:return: Returns nothing
"""
dbStatement = jsonMode.alterAddColumn(database.name, table.name,
column.default)
if dbStatement == 0:
if not self.searchColumn(table, column.name):
if len(table.columns) > 0:
column.number = table.columns[-1].number + 1
table.columns.append(column)
self.writeFile()
print('Table updated successfully')
return
jsonMode.alterDropColumn(database.name, table.name, column.number)
desc = f": Column {column.name} already exists"
ErrorController().addExecutionError(29, 'Execution', desc, noLine,
noColumn)
elif dbStatement == 1:
desc = f": Can't update table {table.name}"
ErrorController().addExecutionError(34, 'Execution', desc, noLine,
noColumn)
elif dbStatement == 2:
desc = f": Database {database.name} does not exist"
ErrorController().addExecutionError(35, 'Execution', desc, noLine,
noColumn)
elif dbStatement == 3:
desc = f": Table {table.name} does not exist"
ErrorController().addExecutionError(27, 'Execution', desc, noLine,
noColumn)