dbs/db4/connect_type is a SAP Parameter attribute which is used to control Type of primary database connection information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
dbs/db4/connect_type profile paramerter attributes
Parameter Name: dbs/db4/connect_type
Description: Type of primary database connection
Default Value:
Parameter Type ( See
IF_PARAMETER_TYPES)
: String(STRING)
Restriction Values:
Parameter Unit:
Parameter Group: Database
CSN Component: BC-DB-DB4
System-Wide parameter: No
Dynamic Parameter: No
Vector Parameter: No
Has Sub-Parameters: No
Check Function Exists: No
Parameter documentation
The parameter determines the connection type of the primary database
connection to the ABAP schema. It only matters if application server and
database server both use IBM i as an operating system. In all other
cases, the connect type will be TCP/IP.
If the parameter is left blank, an appropriate setting is determined
automatically. This setting is recommended.
If dbs/db4/driver_type> == XDN, a local
connect is chosen, whenever application server and database server
reside on the same host, TCP/IP otherwise. SQL Cancel is always
possible.
If dbs/db4/driver_type> == XDA, parameter
dbs/db4/allow_cancel> == 1 will cause
usage of Unix domain sockets if application server and database server
reside on the same host, TCP/IP otherwise. If
dbs/db4/allow_cancel> == 0, a local
connect is chosen.
If application server and database server do not reside on the same
host, TCP/IP is chosen unless
dbs/db4/opticonnect> is set to '1'.
Setting this parameter explicitly works as a hint to the database
driver:
dbs/db4/connect_type = 'U' tries to route over Unix domain sockets,
whenever technically possible.
dbs/db4/connect_type = 'T' routes over TCP/IP sockets.
dbs/db4/connect_type = 'O' tries to route over Opticonnect. This does
not work, if
dbs/db4/driver_type> == XDN. In this case,
see SAP Note 1760552 for more information about how to route the TCP/IP
protocol over Opticonnect. However, this is not recommended.
The final choice is logged in the developer trace:
Connect type = LOCAL | OPTICONNECT | TCPIP SOCKETS | UX-DOMAIN
SOCKETS>
For more information, see SAP Note 1257635.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.