4. Managing Tables and Views : Table Management : Storing BLOBS Inline
 
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Storing BLOBS Inline
When creating a table, you can allocate inline space to store the initial n bytes of data for a large object (blob). This initial portion is physically stored with the blob coupon in the record. If the data for the blob can fit into this area, no extended table is needed to store it.
For example, the inline space in the column definition is specified like: LONG VARCHAR(0) or LONG NVARCHAR(200) or LINESTRING(10000). The size, in bytes, specifies how much space the record can occupy before the blob overflows into the extended table. It does not impose a maximum size on the column.
For the installation, you can set the default size for the inline space by using the following configuration parameters in CBF. For example, if the column data type is specified as simply LONG VARCHAR, the installation default will be used.
The default used depends on the data type:
blob_inl_line_sz
Size for spatial MULTIPOINT, LINESTRING, and MULTILINESTRING types
Limits: 0 to 31968
Default: 1024
blob_inl_poly_sz
Size for spatial POLYGON, MULTIPOLYGON, GEOMETRY, and GEOMETRYCOLLECTION types
Limits: 0 to 31968
Default: 2048
blob_inl_str_sz
Size for LONG VARCHAR, LONG NVARCHAR, and LONG BYTE types
Limits: 0 to 31968
Default: 0
blob_inl_temp_sz
Size for blob temporary result values
Limits: 0 to 31968
Default: 2048
Using inline blobs can improve performance where most of the data for a blob column is relatively small. If the blob data is empty, NULL, or big then we recommend setting the inline size to zero. If most of the data is less than 1024 bytes then an inline value of 1024 is appropriate.