class Menu :
def __init__ ( self ) :
self.methodList = ( self.createDatabase, self.addRecord, self.deleteRecord,
self.bulkLoad, self.join, self.runQuery, self.report1, self.report2 )
self.env = SliceEnv ()
def getDatabaseServices ( self ) :
choice = self.getMenu ()
while choice != 9 :
self.methodList [choice - 1] ()
i = input ( "Press any key to continue" )
choice = self.getMenu ()
def createDatabase ( self ) :
while True :
try :
tableName = input ( "Enter Table Name: " )
while True :
fieldCount = input ( "Enter the number of columns: " )
try :
fieldCount = int ( fieldCount )
if fieldCount < 1 :
raise ValueError
else :
break
except ValueError as e :
print ( "You have entered a wrong value for number of columns" )
print ( "Please enter a correct value" )
schema = list ()
while fieldCount != 0 :
while True :
try :
columnName = input ( "Enter Column Name: " )
while True :
columnType = input ( "Enter the type for %s column: " % columnName )
if columnType == "STRING" :
schema.append ( SliceField ( columnName, SliceField.STRING ) )
break
elif columnType == "INT" :
schema.append ( SliceField ( columnName, SliceField.INT ) )
break
elif columnType == "FLOAT" :
schema.append ( SliceField ( columnName, SliceField.DOUBLE ) )
break
else :
print ( "You have Entered an incorrect type for %s column" % columnName )
print ( "Please try again" )
break
except Exception as e:
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
fieldCount = fieldCount - 1
indexColumn = input ( "Enter an index column ( or press enter key to skip it) : " )
db = self.env.create ( tableName, schema, indexColumn )
self.env.close ()
break
except Exception as e:
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
print ( "%s database has been created" % tableName )
def addRecord ( self ) :
while True :
try :
dbName = input ( "Enter the name of the database to whom you would like to add record: " )
db = self.env.open ( dbName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
newRecord = db.createRecord ()
#Catch exception
while True :
try :
for column in newRecord.recordSchema :
columnName = column.field[0]
while True :
try :
newData = input ( "Enter a value for %s: " % columnName )
newRecord.set ( columnName, newData )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
db.set ( newRecord )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
db.commit ()
print ( "A new record have been added to the database named %s" % dbName )
def deleteRecord ( self ) :
while True :
try :
dbName = input ( "Enter the name of the database from whom you would like to delete record: " )
db = self.env.open ( dbName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
if db.index == None :
print ( "%s do not have an index column. Hence, you are not permitted to delete a record from %s" % (dbName,dbName) )
else :
indexColumnName = db.schema[ db.index ][0]
key = input ( "Enter a value for %s to delete the corresponding record: " % indexColumnName )
try :
result = db.delete ( key )
except Exception as e :
print ( "The following error occurred: %s" %e )
return
if result == True :
db.commit ()
print ( "The record with %s having a value of %s has been deleted from %s" % ( indexColumnName, key, dbName ) )
else :
print ( "No record with %s having a value of %s was found in %s" % ( indexColumnName, key, dbName ) )
def bulkLoad ( self ) :
while True :
try :
dbName = input ( "Enter the name of the database into whom you would like to load the data: " )
db = self.env.open ( dbName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
while True :
try :
fileName = input ( "Enter the name of the bulk load file: " )
db.load ( fileName )
break
except Exception as e :
print ( "The following error occurred relating to your bulk load file: %s" %e )
print ( "Please try again" )
print ( "The data has been loaded from %s into %s database" % ( fileName, dbName ) )
def join ( self ) :
while True :
try :
lhsName = input ( "Enter first database name: " )
lhs = self.env.open ( lhsName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
while True :
try :
rhsName = input ( "Enter second database name: " )
rhs = self.env.open ( rhsName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
userInput = input ( "Enter the join column (press enter to perform default join): " )
try :
if userInput == '' :
joinResult = lhs.join ( rhs )
else :
joinResult = lhs.join ( rhs, userInput )
except Exception as e:
print ( "The following error occurred: %s" %e )
return
print ( "Join result is as follows" )
self.printRecords ( joinResult )
def runQuery ( self ) :
while True :
try :
dbName = input ( "Enter the name of the database on which you would like to perform a query: " )
db = self.env.open ( dbName )
break
except Exception as e :
print ( "The following error occurred: %s" %e )
print ( "Please try again" )
resultColumn = list ()
while True :
value = input ( "Enter the name of a column to display" )
if value != '' :
break
print ( "The result of the query must have atleast one column" )
while value != '' :
resultColumn.append ( value )
value = input ( "Enter the name of a column to display (or press enter key if you have entered all the needed columns): " )
operatingColumn = input ( "Enter the name the column to be used for conditional checking records: " )
operator = input ( "Enter the operation you would like to perform: " )
while True :
if operator == "EQ" :
operator = SliceCondition.EQ
break
elif operator == "LT" :
operator = SliceCondition.LT
break
elif operator == "GT" :
operator = SliceCondition.GT
break
else :
print ( "You have entered a wrong operation" )
print ( "Please enter one among EQ, LT and GT operation" )
operator = input ( "Enter the operation you would like to perform: " )
literalValue = input ( "Enter the value you would like compare the %s values against: " % operatingColumn )
condition = SliceCondition ( operatingColumn, operator, literalValue )
query = SliceQuery ( resultColumn, dbName, condition )
try :
queryResult = db.query ( query )
except Exception as e:
print ( "Your query failed due to the following error: %s" %e )
return
self.printRecords ( queryResult )
def printRecords ( self, re ) :
schema = re[0].recordSchema
widthList = list()
for value in schema :
colName, colType = value.field
if colType == SliceField.INT or colType == SliceField.DOUBLE :
widthList.append (7)
print ( "{0:<7}".format ( colName ), end = '' )
else :
widthList.append (35)
print ( "{0:<35}".format ( colName ), end = '' )
print ()
print ( "{0:-<{width}}".format ( '-', width = sum (widthList) ) )
for value in re :
currentRecord = value.record
for i, element in enumerate ( currentRecord ) :
print ( "{0:<{width}}".format ( element, width = widthList[i] ), end = '' )
print ()
def report1 ( self ) :
pass
def report2 ( self ) :
pass
def getMenu ( self ) :
print ()
print ( "Slice database testing menu" )
print ( "1. Create Database" )
print ( "2. Add Record" )
print ( "3. Delete Record" )
print ( "4. Bulk Load" )
print ( "5. Natural Join" )
print ( "6. Run Query" )
print ( "7. Report 1" )
print ( "8. Report 2" )
print ( "9. Exit" )
print ()
while True :
choice = input ( "Enter your choice: ")
try :
choice = int ( choice )
if choice < 1 or choice > 9 :
raise ValueError
break
except ValueError as e :
print ( "You have entered a wrong choice" )
print ( "Please try again" )
print ()
return choice
def __init__ ( self ) : self.methodList = ( self.createDatabase, self.addRecord, self.deleteRecord, self.bulkLoad, self.join, self.runQuery, self.report1, self.report2 ) self.env = SliceEnv ()
from SliceEnv import SliceEnv
from SliceDB import SliceDB
from SliceField import SliceField
import os
env = SliceEnv()
menuRunning = True
while menuRunning:
print "1. Create database"
print "2. Update Record"
print "3. Add record"
print "4. Delete Record"
print "5. Bulk load"
print "6. Display Join"
print "7. Run Query"
print "8. Report 1"
print "9. Report 2"
print "10. Exit"
instruction = raw_input("plase enter an integer : ")
try:
instruction = int(instruction)
if instruction == 1:
tableName = raw_input("plase enter new table name : ")
if tableName == "":
print "you have to enter a name"
continue
numOfField = raw_input("count of the number of fields : ")
try:
numOfField = int(numOfField)
except ValueError:
print ("That's not an Integer!")
