Db_Manager Object |
|
This object provides a database-independent interface for retrieving and updating table information. Each method includes an argument to identify the source (or destination) database. The value of this argument can be specified using the following code:
Example:
dbConstants =new("*dict/db_constants")
tag$="ado"
aDatabaseID=dbConstants'getDatabaseID(tag$)
The database tag$ may be one of the following:
|
ado |
Microsoft SQL-Server interface (ADO) |
|
db2 |
IBM DB2 interface (DB2) |
|
oci |
Oracle interface (OCI) |
|
odb |
ODBC interface |
|
mysql |
MYSQL interface (MYSQL) |
|
pvxddf |
PxPlus DDF/DDE Files |
|
pvxdb |
PxPlus embedded Data Dictionary information from a physical file |
Db_Manager contains three primary methods:
Tblinfo Methods |
Description |
ReadDefn( ) |
Reads the table definition from the providex.ddf and providex.dde files, an external database, or a physical file with an embedded dictionary definition (determined by sourcedb parameter) and stores it in a temporary location. |
CreateTable( ) |
Retrieves the table definition from the temporary location and either creates a physical file with an embedded dictionary definition, a table in an external database, or the providex.ddf/providex.dde definitions (determined by destinationdb parameter). |
DropTable( ) |
Drops a table from the providex.ddf/providex.dde files, an external database or a physical file with an embedded dictionary definition (determined by destinationdb parameter). |
Different parameter values are used for these methods depending on the source or destination database. See the sample programs below.
The following sample programs illustrate the functionality of the Db_Manager Object:
Example 1
Retrieving the table definition from a Microsoft SQL-Server database (ADO):
db=new("*dict/db_manager")
dbConstants=new("*dict/db_constants")
Table$="Customer"
ConnectOpt$="user=sa;pswd=admin;db=test"
DSN$="ws2003-x86-pdb.pvx.com"
TableOk=db'ReadDefn(dbConstants'getDatabaseID("ado"),Table$,ConnectOpt$,DSN$)
Removing/creating a new table definition in providex.ddf/providex.dde files:
Ddfpath$="c:\demo\data"
FilePath$="cstfile"
UpdateTable=0
GroupName$="Customers"
Db'Droptable(dbConstants'getDatabaseID("pvxddf"),Table$,ddfpath$) ! remove table definition if it exists
Db'CreateTable(dbConstants'getDatabaseID("pvxddf"),ddfpath$,FilePath$,UpdateTable,GroupName$)
Updating the table in the providex.ddf/providex.dde files:
Ddfpath$="c:\demo\data"
FilePath$=""
UpdateTable=1
GroupName$="" db'CreateTable(dbConstants'getDatabaseID("pvxddf"),ddfpath$,FilePath$,UpdateTable,GroupName$)
Example 2
Retrieving the table definition from the providex.ddf/providex.dde files:
Db=new("*dict/db_manager")
dbConstants=new("*dict/db_constants") Table$="Customer"
Ddfpath$="c:\demo\data"
TableOk=db'ReadDefn(dbConstants'getDatabaseID("pvxddf"),Table$,Ddfpath$)
Updating the physical file:
FilePath$="cstfile" UpdateTable=1
db'CreateTable(dbConstants'getDatabaseID("pvxddf"),FilePath$,UpdateTable)
Updating the table in the Microsoft SQL-Server database (ADO):
ConnectOpt$="user=sa;pswd=admin;db=test"
DSN$="ws2003-x86-pdb.pvx.com"
UpdateTable=1
db'CreateTable(dbConstants'getDatabaseID("ado"),Table$,ConnectOpt$,DSN$,UpdateTable)