SQLAPI++ supports four types for working with this kind of data (see Server specific notes later on this page for details about how SQLAPI++ maps this types on a different SQL platforms):

Working with Long or Lob data includes the following:

• Binding Long or Lob data into input variables (SQL statements) or input parameters (stored procedures/functions)
• Reading Long or Lob data (from fields in result set or from output parameters of stored procedure)

Binding Long or Lob Data

Let say we want to update BLob field named FBLOB from table named TEST where some other field named FKEY is equal to 'KEY':

UPDATE TEST SET FBLOB = :fblob WHERE FKEY = 'KEY'

Field should be updated with the content of a file named 'blob.bin'.

First, initialize the command object:

SACommand cmd(
    &con, 
    _TSA("UPDATE TEST SET FBLOB = :fblob WHERE FKEY = 'KEY'"));

For more information see Execute SQL Statement.

Next step is to actually bind the content of a file into input variable. The following code binds parameter :fblob with value of file content read:

SAString sContent = SomeFunctionThatReadFileContent("blob.bin");
cmd.Param(_TSA("fblob")).setAsBLob() = sContent;

All that we need now is to execute a query:

cmd.Execute();

For using piecewise capabilities of SQLAPI++ for binding Long or Lob types see example.

Reading Long or Lob data

Let's say we want to retrieve BLob field named FBLOB from table named TEST where some other field named FKEY (primary key) is equal to 'KEY':

SELECT FBLOB FROM TEST WHERE FKEY = 'KEY'

Field should be read into a file named 'blob.bin'.

First, create command object:

SACommand cmd(
    &con,
    _TSA("SELECT FBLOB FROM TEST WHERE FKEY = 'KEY'"));

For more information see Execute SQL Statement.

Then execute the query:

cmd.Execute();

Finally, fetch the row(s) and access BLob data:

while(cmd.FetchNext())
{
    SAString sBLob = cmd.Field(_TSA("FBLOB")).asBLob();
    SomeFunctionToSaveBLobToFile("blob.bin", sBLob);
}

For using piecewise capabilities of SQLAPI++ for reading Long or Lob types see this example.