isCOBOL Evolve : Appendices : Library Routines : ESQL$BLOB
ESQL$BLOB
The ESQL$BLOB library routine provides a number of functions to handle BLOB data in ESQL programs.
Syntax:
 CALL "ESQL$BLOB" USING opCode 
                        parameters
                 GIVING returnCode
Parameters:
opCode
It is the function to be executed. Valid values, defined in iscobol.def, are:
 
Read BLOB data from a file on disc.
Write the content of a BLOB into a file on disc.
Free memory initializing the BLOB handle.
parameters
Parameters depend on the opcode.
Return code:
returnCode definition and meaning depend on the opcode.
Examples:
Example - The following program creates a test table and stores the file img1.bmp inside it as a blob. After it, the program reads the previously inserted record and writes the blob to a file named blob.bmp.
       PROGRAM-ID. readwriteblob.
 
       WORKING-STORAGE SECTION.
       copy "SQLCA".
       copy "iscobol.def".
 
       01 W-REC.
        03 W-KEY   pic 9(4).
        03 W-DATA  pic x(30).
        03 W-BLOB  HANDLE.
 
       PROCEDURE DIVISION.
       Main.
           CALL "ESQL$BLOB" USING GET-BLOB-FROM-FILE, W-BLOB,"img1.bmp".
 
           EXEC SQL
                CONNECT
           END-EXEC
 
           EXEC SQL 
                DROP TABLE IS_TABLE
           END-EXEC
 
           EXEC SQL
                CREATE TABLE IS_TABLE
                             (IS_KEY INT NOT NULL,
                              IS_DATA CHAR(6),
                              IS_BLOB BLOB)
           END-EXEC
 
           EXEC SQL
                ALTER TABLE IS_TABLE ADD PRIMARY KEY (IS_KEY)
           END-EXEC
 
           EXEC SQL INSERT INTO IS_TABLE VALUES (1, 'row1',
                                                 :W-BLOB)
           END-EXEC
 
           CALL "ESQL$BLOB" USING FREE-BLOB-HANDLE, W-BLOB.
 
           EXEC SQL
                SELECT * INTO :W-KEY, :W-DATA, :W-BLOB
                             FROM IS_TABLE
                             WHERE IS_KEY = 1
           END-EXEC
 
           CALL "ESQL$BLOB" USING PUT-BLOB-INTO-FILE, W-BLOB, "blob.bmp".
 
           EXEC SQL
                DISCONNECT
           END-EXEC
 
           GOBACK.