def join(dbName1, dbName2, joinCol):
env = sliceEnv.sliceEnv()
db1 = env.open(dbName1)
db2 = env.open(dbName2)
result = db1.join(db2,joinCol)
newSchema = result[0]
joinDB = result[1]
strShow=""
tempSch = []
for field in newSchema:
name = field.getName()
tempSch.append(name)
var = "|"
schStr = var.join(tempSch)
strShow += schStr+"\n"
for key in joinDB.keys():
recordObj = joinDB[key]
var = "|"
temp = []
for i in range(len(recordObj.record)):
tempValue = str(recordObj.record[i])
temp.append(tempValue)
recStr = var.join(temp)
strShow += recStr+"\n"
return strShow
def addRecord(dbName,values):
env = sliceEnv.sliceEnv()
sliceDB = env.open(dbName)
schema = sliceDB.schema
indCol = sliceDB.indexColumn
''' if is for the Database with no index column, else is for the database with index column.'''
if indCol == "":
record = sliceDB.createRecord()
msg = record.setValue(values)
if msg == "":
sliceDB.setRecord(record)
env.close(dbName)
return "add record successfully!"
else:
return msg
else:
for i in range(len(schema)):
if schema[i].getName() == indCol:
v = values[i].split("|",1)
v1= v[1]
if v1 not in sliceDB.database:
if v1!= "":
record = sliceDB.createRecord()
msg = record.setValue(values)
if msg == "":
sliceDB.setRecord(record)
env.close(dbName)
return "add record successfully!"
else:
return msg
else:
return "Failed. The key cannot be empty."
else:
return "Failed. This key has already exist, please check.\n If you want to update the record, please choose update."
def keyExist(dbName):
env = sliceEnv.sliceEnv()
db = env.dbInfo[dbName]
indexCol = db.indexColumn
if indexCol == "" :
return False
else:
return True
def bulkLoad(dbName,fileName):
env = sliceEnv.sliceEnv()
sliceDB= env.open(dbName)
msg = sliceDB.load(fileName)
if msg == "":
env.close(dbName)
return "load file successfully!"
else:
return msg
def createDatabase(name, count, colInfo, index):
dbSchema = createSchema(count, colInfo)
env = sliceEnv.sliceEnv()
if name not in env.dbInfo:
env.createDB(name, dbSchema, index)
msg = "create successfully."
else:
msg = "this table name has already exist."
env.close(name)
return msg
def deleteRecord(dbName, key):
env = sliceEnv.sliceEnv()
sliceDB = env.open(dbName)
if key in sliceDB.database:
msg = sliceDB.deleteRecord(key)
if msg == "":
env.close(dbName)
return "delete record successfully!"
else:
return msg
else:
return "The key of the delete record was wrong! There is no such record."
def lookupRecord(dbName,key):
env = sliceEnv.sliceEnv()
sliceDB = env.open(dbName)
if key in sliceDB.database:
rec = sliceDB.getRecord(key)
schema = rec.schema
recordValue = rec.record
strShow = ""
for i in range(len(schema)):
strShow += schema[i].getName()+": "+ str(recordValue[i])+"\n"
return strShow
else:
return "The key of the lookup record was wrong! There is no such record."
def runQuery(dbName, displayCol, condition):
env = sliceEnv.sliceEnv()
sliceDB = env.open(dbName)
condList = condition.split("|", condition.count("|"))
seleCol = condList[0]
literal = condList[2]
displayList = displayCol.lower().split("|",condition.count("|"))
fieldType = ""
nameList = []
for i in range(len(sliceDB.schema)):
field = sliceDB.schema[i]
nameList.append(field.getName())
if field.getName() == seleCol:
fieldType = field.getType()
if seleCol not in nameList:
return "there is no such select column"
for disCol in displayList:
if disCol not in nameList:
return "there is no such display column"
if ((fieldType == "INT") and (literal.isdigit())):
dispCol = displayCol.lower()
result = sliceDB.query(dispCol, condition)
strR = displayCol+"\n"
for i in range(len(result)):
strR += result[i]+"\n"
return strR
elif ((fieldType == "FLOAT") and (isFloat(literal))):
dispCol = displayCol.lower()
result = sliceDB.query(dispCol, condition)
strR = displayCol
for i in range(len(result)):
strR += result[i]+"\n"
return strR
elif (fieldType == "STRING"):
dispCol = displayCol.lower()
result = sliceDB.query(dispCol, condition)
strR = displayCol+"\n"
for i in range(len(result)):
strR += result[i]+"\n"
return strR
else:
return "The literal should be with the same type as the select column."
def updateRecord(dbName, values, key):
#print(values)
temp=[]
for i in range(len(values)):
info = values[i].split("|",1)
if info[1]!="":
temp.append(values[i])
#print(temp)
env = sliceEnv.sliceEnv()
sliceDB = env.open(dbName)
if key in sliceDB.database:
record = sliceDB.getRecord(key)
msg = record.setValue(temp)
if msg == "":
sliceDB.setRecord(record)
env.close(dbName)
return "update record successfully!"
else:
return msg
else:
return "The key of the update record was wrong! There is no such record."
def getIndCol(dbName):
env =sliceEnv.sliceEnv()
db = env.dbInfo[dbName]
index = db.indexColumn
return index
def getSchema(dbName):
env =sliceEnv.sliceEnv()
if dbName in env.dbInfo:
db = env.dbInfo[dbName]
schema = db.schema
return schema
def checkDB(dbName):
env = sliceEnv.sliceEnv()
if dbName in env.dbInfo :
return True
else:
return False
def saveAllDB():
env = sliceEnv.sliceEnv()
for key in env.dbInfo.keys():
db = env.dbInfo[key]
db.writeIntoFile()