Updated on 2023-10-23 GMT+08:00

Binary Types

Table 1 lists the binary data types supported by GaussDB.

Table 1 Binary types

Name

Description

Storage Space

BLOB

Binary large object.

Currently, BLOB only supports the following external access APIs:

  • DBE_LOB.GET_LENGTH
  • DBE_LOB.READ
  • DBE_LOB.WRITE
  • DBE_LOB.WRITE_APPEND
  • DBE_LOB.COPY
  • DBE_LOB.ERASE

For details about the APIs, see DBE_LOB.

NOTE:

Column storage cannot be used for the BLOB type.

The maximum size is 32 TB (that is, 35184372088832 bytes).

RAW

Variable-length hexadecimal string.

NOTE:

Column store cannot be used for the raw type.

4 bytes plus the actual hexadecimal string. Its maximum length is 1073733621 bytes (1 GB – 8203 bytes).

BYTEA

Variable-length binary string.

4 bytes plus the actual binary string. Its maximum length is 1073733621 bytes (1 GB – 8203 bytes).

BYTEAWITHOUTORDERWITHEQUALCOL

Variable-length binary character string (new type for the encryption feature. If the encryption type of the encrypted column is specified as deterministic encryption, the column type is BYTEAWITHOUTORDERWITHEQUALCOL). The original data type is displayed when the encrypted table is printed by running the meta command.

4 bytes plus the actual binary string. The maximum value is 1,073,741,771 bytes (1 GB minus 53 bytes).

BYTEAWITHOUTORDERCOL

Variable-length binary character string (new type for the encryption feature. If the encryption type of the encrypted column is specified as random encryption, the column type is BYTEAWITHOUTORDERCOL). The original data type is displayed when the encrypted table is printed by running the meta command.

4 bytes plus the actual binary string. The maximum value is 1,073,741,771 bytes (1 GB minus 53 bytes).

_BYTEAWITHOUTORDERWITHEQUALCOL

Variable-length binary string, which is a new type for the encryption feature.

4 bytes plus the actual binary string. The maximum value is 1,073,741,771 bytes (1 GB minus 53 bytes).

_BYTEAWITHOUTORDERCOL

Variable-length binary string, which is a new type for the encryption feature.

4 bytes plus the actual binary string. The maximum value is 1,073,741,771 bytes (1 GB minus 53 bytes).

  • In addition to the size limitation on each column, the total size of each tuple is 1073733621 bytes (1 GB to 8203 bytes).
  • BYTEAWITHOUTORDERWITHEQUALCOL, BYTEAWITHOUTORDERCOL, _BYTEAWITHOUTORDERWITHEQUALCOL, and _BYTEAWITHOUTORDERCOL cannot be directly used to create a table.

Example:

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-- Create a table.
openGauss=# CREATE TABLE blob_type_t1 
(
    BT_COL1 INTEGER,
    BT_COL2 BLOB,
    BT_COL3 RAW,
    BT_COL4 BYTEA
) ;

-- Insert data.
openGauss=# INSERT INTO blob_type_t1 VALUES(10,empty_blob(),
HEXTORAW('DEADBEEF'),E'\\xDEADBEEF');

-- Query data in the table.
openGauss=# SELECT * FROM blob_type_t1;
 bt_col1 | bt_col2 | bt_col3  |  bt_col4   
---------+---------+----------+------------
      10 |         | DEADBEEF | \xdeadbeef
(1 row)

-- Delete the table.
openGauss=# DROP TABLE blob_type_t1;