Editing the Configurations During Migration from PostgreSQL to GaussDB

PostgreSQL DDLs support PARALLEL, but GaussDB DDLs does not support it.

PARALLEL

Comment PARALLEL.

The unit of the PostgreSQL character type length is character. In PostgreSQL compatibility mode, the unit of the GaussDB character type length is character. In other compatibility modes, the unit of the GaussDB character type length is byte.

Character data type conversion

For PostgreSQL compatibility mode, do not convert the character type length. For other compatibility modes, convert char/varchar to nvarchar2.

GaussDB reserves the case of object names and uses double quotation marks to quote object names.

Object names case format

Recommended value: Ensure that the case of the object name is the same as that of the source database.

Database partitioned tables in PostgreSQL are incompatible with those in GaussDB.

Convert partitioned table

Recommended value: Convert declaratively-partitioned tables.

Impact: When the GaussDB syntax is used to rewrite partitioned tables, advanced features of PostgreSQL partitioned tables cannot be converted, which is not equivalent conversion. Only declaratively-partitioned tables are supported, and partitioned tables implemented through table inheritance are not supported. Only CREATE TABLE child_table_name PARTITION OF parent_table_name" is supported to create subpartitions. Only level-1 partitions are supported. A partition key only supports one column and does not support expressions.