Help Center/ GaussDB/ Service Overview/ Compatibility with Oracle/ Distributed Instances/ Pseudocolumns
Updated on 2024-05-14 GMT+08:00
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Pseudocolumns

GaussDB is compatible with sequence and rownum pseudocolumns. Other pseudocolumns are not supported.

Sequence Pseudocolumns

Table 1 Sequences

No.

Oracle

GaussDB

Difference

1

currval

Supported, with differences.

It is implemented as a function in GaussDB. The call mode is compatible with Oracle.

2

nextval

Supported, with differences.

It is implemented as a function in GaussDB. The call mode is compatible with Oracle.

ROWNUM Pseudocolumn

Table 2 rownum

No.

Oracle

GaussDB

Difference

1

rownum

Supported, with differences.

When Oracle uses rownum in the left, right, and full join conditions for filtering, the performance varies according to the conditions. The rownum condition may be ignored or partially ignored. However, GaussDB filters the results after left, right, and full join.

XMLDATA Pseudocolumn

Table 3 xmldata

No.

Oracle

GaussDB

1

xmldata

Not supported
Parent topic: Distributed Instances