Teradata ODBC Driver Advanced Options

ODBC Driver for Teradata® User Guide

brand
Teradata Tools and Utilities
prodname
ODBC Driver for Teradata
vrm_release
16.20
category
User Guide
featnum
B035-2526-108K

Click the Advanced button in the Warning area of the Teradata ODBC Driver Options dialog box to see further options available. The Advanced Options dialog box appears. The table below lists the advanced options.

Advanced Options Caution

It is strongly recommended NOT to change the settings in the Advanced Options dialog box.


Field, Check Box, or Button Description
Maximum Response Buffer Size Default = 65536 (64K)

Enter the value used to try to limit the Teradata response buffer size for SQL requests. This value can be adjusted dynamically if Teradata cannot send a result within the limited packet size defined.

See the “MaxRespSize=<integer 16775168>” option in Teradata DSN Options.

TDMST Port Number Default = 1025

Lists the port number to use to access Teradata Database. Do not change this value unless instructed to do so by Technical Support.

See the “TDMSTPortNumber=<integer>” option in Teradata DSN Options.

Translation DLL Name Specifies the translation DLL path. Translation DLL is used to convert between session character set and application character set.

See Session Character Sets and Translation DLLs.

Translation Option Specifies the translation DLL option. The option is used by translation DLL.

See Session Character Sets and Translation DLLs.

Login Timeout Default = 20

Defines a value corresponding to the number of seconds to wait when establishing a virtual circuit with Teradata for login. Enter an integer value.

See Teradata DSN Options.

ProcedureWithPrintStmt Default = N

Activates the print option when creating stored procedures.

See the “PrintOption=[N | P]” option in Teradata DSN Options.

ProcedureWithSPLSource Default = Y

Specifies the SPL option when creating stored procedures.

See the “SplOption=[Y | N]” option in Teradata DSN Options.

Data Source DNS Entries The Data Source DNS Entries DSN option notifies the ODBC Driver for Teradata how many entries are defined in DNS for the database name. The initial value of this option controls how the ODBC Driver for Teradata resolves database names to IP addresses. If this value is not set, the default value is undefined (empty). If multiple database names are provided in ODBC DSN, the Data Source DNS Entries option is applicable to all names.
If a database is identified by IP address instead of a name in the ODBC DSN or connection-string, the Data Source DNS Entries option is ignored. The database is identified in the Name(s) or IP address(es) field described in ODBC Driver Setup Parameters.

Data Source DNS Entries=undefined (default setting) is recommended for best results. This setting enables the ODBC Driver for Teradata to lookup DNS dynamically and find all available COPs for a given database name. Using this approach, ODBC Driver for Teradata will automatically detect new nodes added to the Teradata database (and DNS) in the future, without ODBC modification. For more information, see Resolving a Data Source Name.

Data Source DNS Entries= 0 indicates that DNS does not contain cop entries for the database name. The database name will only be resolved by itself. No attempt will be made to resolve using a cop suffix. This behavior can be desirable in an environment utilizing DNS to load balance. When DNS is used for load balancing, administrators can configure DNS to provide a different IP address or multiple IP addresses in different order each time the database name is resolved using DNS.

Data Source DNS Entries= value. Entering a non-zero value indicates that DNS contains cop entries for the database name and the last cop entry is value. The first connection attempt will chose a random number between 1 and value. Each subsequent connection will then increment to the next number (round-robin). This approach will not encounter costly DNS resolution failures (how costly depends on how the DNS is configured). However, if additional entries are added to DNS at a later time, they will not be discovered by the ODBC Driver for Teradata unless the supplied value is increased.

Use TCP_NODELAY Default = Selected

Valid for the Teradata DSN in ODBC Driver for Teradata.

Transmission Control Protocol (TCP) provides an option called TCP_NODELAY to control the transmission of data.

See the “TCPNoDelay=[Yes | No]” option in Teradata DSN Options.

Use NULL for Catalog Name Default = Cleared

When this option is selected – NULL values are assumed for the Catalog Name parameters in any of the Catalog API functions, even if the application passes a value.

When this option is cleared and a value is passed for the Catalog Name parameter instead of NULL – ODBC Driver for Teradata returns an error because catalogs are not supported by Teradata Database.

Enable Read Ahead Default = Selected

When this option is selected - the ODBC Driver reads ahead by requesting the next response message from the database when the current response message being processed is not the last. The database can have one request active for each session at any point in time. An active request is either an SQL request which is executing or a request for the next part of the result from an earlier SQL request.

When this option is cleared - the ODBC Driver only requests the next response message from the database when the current response message has been processed by the driver.

Retry system calls (EINTR) Default = Selected

When this option is cleared – the ODBC Driver returns an SQL_ERROR to the ODBC Application. The ODBC Application is responsible for recovery from the interrupted socket system calls.When this option is selected – the ODBC Driver is responsible for retrying the socket system calls when they have been interrupted by some event such as a SIGALRM.

SLOB Options group box
Max Single LOB Bytes Unsigned int 32

Default value is 4000:

The maximum size in byte for LOB data to be returned as SLOBs for each row. 0 means the feature is disabled.

Max Total LOB Bytes Per Row Unsigned int 32

Default value is 65536:

The maximum size in byte for LOB data to be returned as SLOBs for each row. 0 means the feature is disabled.

Use Sequential Retrieval Only Boolean

Default values is false:

This is a performance-related setting. It indicates that only sequential retrieval or random access will be used.

If sequential retrieval only is enabled, the driver will not cache the data for SLOBs. It retrieves data faster by skipping the caching step.

It also means if sequential only is set and the client performs random access, performance will be downgraded because the data is retrieved using a deferred LOB.

If random access is required, each SLOB data will be cached for later use/reuse. This slows the retrieval process, but permits the client to return to the data at a later time.

Custom Options group box
Use DATE data for TIMESTAMP parameters Default = Cleared

When this option is selected– ODBC Driver for Teradata is directed to send DATE data for parameters bound as SQL_C_TIMESTAMP and SQL_TIMESTAMP.

This option should not be enabled for applications that are not using Microsoft Access Jet databases.

This option should only be selected for this circumstance, as this results in truncation of SQL_C_TIMESTAMP data to contain only the DATE portion.

When this option is selected – the ODBC DriverEnable Custom Catalog Mode for 2.x Applications Default = Cleared

Provides backwards compatibility for ODBC 2.x applications that have taken advantage of a defect in the ODBC Driver where the functionality of the Catalog APIs are noncompliant with the ODBC Programmer's Reference specification.

The behavior when a NULL value is passed to the SQLTables API for the SchemaName argument results in a search for tables belonging to the userid, DBC, and default database schema names, rather than a % search pattern as noted in the ODBC Programmer's Reference specification.

Return Empty string in CREATE_PARAMS column for SQL_TIMESTAMP Default = Cleared

Returns an empty string for the CREATE_PARAMS column of SQLGetTypeInfo for SQL_TIMESTAMP data type, and disallows MC-ACCESS from using any TIMESTAMP precision value in Create Table text.

Return max. CHAR/VARCHAR length as 32K Default = Cleared

Returns a value of 32000 (in general, could be 64000 also) for COLUMN_SIZE column of SQLGetTypeInfo for SQL_CHAR and SQL_VARCHAR data types. This allows MS-ACCESS to handle column size value returned by ODBC Driver for Teradata without any numeric overflow.

Upon completion, return to each previous screen in the sequence by clicking the OK button.

After entering the required information into the Teradata Database ODBC Driver 16.20 DSN Setup dialog box, click OK.

The data source that you just configured displays in the user Data Sources list of the ODBC Data Source Administrator dialog box.

To continue adding data sources, repeat the process.