HP 3000 Manuals

ALLBASE/SQL FORTRAN Application Programming Guide

Defining LONG Columns with a CREATE TABLE or ALTER TABLE Command 

Following is the new portion of the CREATE TABLE or ALTER TABLE command
syntax for specifying a LONG column column definition. 
A maximum of 40 such LONG columns may be defined for a single table.

(ColumnName LONG {BINARY   }(ByteSize) [IN DBEFileSet] [NOT NULL] )
                 {VARBINARY}

[,...]

When you create or add a LONG column to a table you have the option of
specifying the DBEFileSet in which it is to be stored.  Because LONG
column data may take up a large chunk of a given DBEFile's data pages,
placing LONG column data in a separate DBEFileSet is strongly
advantageous from the standpoint of storage as well as performance.

If the IN DBEFileSetName clause is not specified for a LONG column, this
column's data is by default stored in the same DBEFileSet as its related
table.


NOTE  It is recommended that you do not use the SYSTEM DBEFileSet in
      which to store your data, as this could severely impact database
      performance.


In the following example, LONG column data for PartPicture will be stored
in PartPictureSet while data for columns PartName and PartNumber will be
stored in PartsTableSet.

     CREATE TABLE PartsTable (
                  PartName CHAR(10),
                  PartNumber INTEGER,
                   PartPicture LONG VARBINARY(1000000) IN PartPictureSet) 
                IN PartsTableSet 

The next command specifies that data for new LONG column, PartModule, be
stored in PartPictureSet.

     ALTER TABLE PartsTable
             ADD  PartModule LONG VARBINARY(70000) IN PartPictureSet 

See the "BINARY Data" section of the "Host Variables" chapter for more
information on using BINARY and VARBINARY data types in long columns.

Now that you have defined our table, let's see how to put data into it
and to specify where data goes when it is retrieved.

MPE/iX 5.0 Documentation