Click here to view and discuss this page in DocCommentXchange. In the future, you will be sent there automatically.

SQL Anywhere 17 » SQL Anywhere Server - Database Administration » Database configuration » Database options » Alphabetical list of database options

default_timestamp_increment option

Specifies the number of microseconds to add to a column that has a default value of TIMESTAMP or UTC TIMESTAMP to keep values in the column unique when a row containing the column is inserted or updated.

Allowed values

Integer, between 1 and 1000000 inclusive

Default

1

Scope
  PUBLIC role For current user For other users
Allowed to set permanently? Yes, with SET ANY PUBLIC OPTION Yes Yes, with SET ANY PUBLIC OPTION
Allowed to set temporarily? Yes, with SET ANY PUBLIC OPTION Yes (current connection only) No
Remarks

Since a TIMESTAMP value is precise to six decimal places in SQL Anywhere, by default 1 microsecond (0.000001 of a second) is added to differentiate between two identical TIMESTAMP or TIMESTAMP WITH TIME ZONE values.

Settings for this database option do not apply to TIMESTAMP columns that have been declared with the DEFAULT CURRENT TIMESTAMP attribute.

When several rows containing a column with the DEFAULT TIMESTAMP or DEFAULT UTC TIMESTAMP attribute are updated and the column itself is not explicitly updated, the column receives a unique value for each row being updated. For example, three rows containing a column of type TIMESTAMP WITH TIME ZONE with the DEFAULT UTC TIMESTAMP attribute are updated. The rows are updated at '2011-04-01 12:47:52.724000+00:00', however each row contains a unique UTC TIMESTAMP value.

2011-04-01 12:47:52.724000+00:00
2011-04-01 12:47:52.724001+00:00
2011-04-01 12:47:52.724002+00:00

Some software, such as Microsoft Access, truncates TIMESTAMP values to three decimal places, making valid comparisons a problem. You can set the truncate_timestamp_values option to On to specify the number of decimal place values the database server stores to maintain compatibility.

For MobiLink synchronization, if you are going to set this option, set it before performing the first synchronization.