Database

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The Database object provides general information about Databases in the process instance. These are:


Syntax

       public class Database


Members

Schema GetSchema(string name)

Retrieves a schema by name of the associated schema diagram.



Syntax

       public class Schema


Members

object Execute(string cmd)

Execute an SQL-statement on the schema

DBReader Select(string cmd)

Execute an SQL-statement on the schema which returns data

void Close()

Close the schema


Syntax

       public class DBReader


Members

bool IsClosed()

Indicates if the reader has been closed

bool Read()

Read the next row from the database

void Close()

Close the reader

void Dispose()

Disposes the reader. Its important in non-sandboxed environments to dispose the reader to avoid memory leaks

object GetValue(int index)

Get the value of the column of the current row by index


Sample

This sample sets and updates information about a person


s = Database.GetSchema("Datastorage")

hasData = False

with s.Select("select Id, Name, Age from Person") as reader:

 while reader.Read():

   hasData = True

   ProcessInstance.Warn("DBData:"+str(reader.GetValue(1)))

   mId = reader.GetValue(0)

   mAge = reader.GetValue(2)

if hasData:

 s.Execute("UPDATE Person SET Age=%d WHERE ID=%d" % (mAge + 1, mId))

else:

 s.Execute("INSERT INTO Person (Name,Age) VALUES ('Frank',45)")

s.Close()