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SQL Anywhere 11.0.1 (中文) » SQL Anywhere 服务器 - 编程 » SQL Anywhere 数据访问 API » SQL Anywhere C API 参考 » SQL Anywhere C API 示例

 

send_retrieve_full_blob.cpp

此示例说明如何在一个块中插入和检索 blob。

// *********************************************************************
// Copyright 1994-2008 iAnywhere Solutions, Inc.  All rights reserved.
// This sample code is provided AS IS, without warranty or liability
// of any kind.
//
// You may use, reproduce, modify and distribute this sample code
// without limitation, on the condition that you retain the foregoing
// copyright notice and disclaimer as to the original iAnywhere code.
//
// *********************************************************************
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include "sacapidll.h"

int main( )
{
    SQLAnywhereInterface api;
    a_sqlany_connection *conn;
    a_sqlany_stmt       *stmt;
    unsigned int         I;
    unsigned char       *data;
    size_t               size = 1024*1024; // 1MB blob
    int                  code;
    a_sqlany_data_value  value;
    int                  num_cols;
    unsigned int         max_api_ver;
    a_sqlany_bind_param  param;

    if( !sqlany_initialize_interface( &api, NULL ) ) {
        printf( "Could not initialize the interface!\n" );
        exit( 0 );
    }

    assert( api.sqlany_init( "my_php_app", SQLANY_CURRENT_API_VERSION, &max_api_ver ) );
    conn = api.sqlany_new_connection();

    if( !api.sqlany_connect( conn, "uid=dba;pwd=sql" ) ) {
        char buffer[SACAPI_ERROR_SIZE];
        code = api.sqlany_error( conn, buffer, sizeof(buffer) );
        printf( "Could not connection[%d]:%s\n", code, buffer );
        goto clean;
    }

    printf( "Connected successfully!\n" );

    api.sqlany_execute_immediate( conn, "drop table my_blob_table" );
    assert( api.sqlany_execute_immediate( conn, "create table my_blob_table (size integer, data long binary)" ) != 0);

    stmt = api.sqlany_prepare( conn, "insert into my_blob_table( size, data ) values( ?, ?)" );
    assert( stmt != NULL );

    data = (unsigned char *)malloc( size );
    // initialize the buffer
    for( I = 0; I < size; I++ ) {
        data[i] = I % 256;
    }


    // initialize the parameters
    api.sqlany_describe_bind_param( stmt, 0, &param );
    param.value.buffer = (char *)&size;
    param.value.type   = A_VAL32;               // This needs to be set as the server does not
    // know what data will be inserting.
    api.sqlany_bind_param( stmt, 0, &param );

    api.sqlany_describe_bind_param( stmt, 1, &param );
    param.value.buffer = (char *)data;
    param.value.length = &size;
    param.value.type   = A_BINARY;              // This needs to be set for the same reason as above.
    api.sqlany_bind_param( stmt, 1, &param );

    assert( api.sqlany_execute( stmt ) );

    api.sqlany_free_stmt( stmt );

    api.sqlany_commit( conn );

    stmt = api.sqlany_execute_direct( conn, "select * from my_blob_table" );
    assert( stmt != NULL );

    assert( api.sqlany_fetch_next( stmt ) == 1 );

    num_cols = api.sqlany_num_cols( stmt );

    assert( num_cols == 2 );

    api.sqlany_get_column( stmt, 0, &value );

    assert( *((int*)value.buffer) == size );
    assert( value.type == A_VAL32 );

    api.sqlany_get_column( stmt, 1, &value );

    assert( value.type == A_BINARY );
    assert( *(value.length) == size );

    for( I = 0; I < (*value.length); I++ ) {
        assert( (unsigned char)(value.buffer[i]) == data[i]);
    }

    assert( api.sqlany_fetch_next( stmt ) == 0 );
    api.sqlany_free_stmt( stmt );

    api.sqlany_disconnect( conn );

clean:
    api.sqlany_free_connection( conn );

    api.sqlany_fini();

    sqlany_finalize_interface( &api );
    printf( "Success!\n" );
}