BLOB到字节阵列转换目标C

Question

我有提起表，其中，值存储为BLOB类型。我需要将它作为二进制数组，以便我可以从BLOB中的不同字节位置获取不同的值。任何帮助表示赞赏。

Answer 1

// Get the start and length of the blob. 
// (remember column indexes are 0-based when fetching the value 
// but 1-base when binding - yeah cheers!) 
uint8_t *data = (uint8_t *)sqlite3_column_blob(stmt, columnIndex); 
size_t length = (size_t)sqlite3_column_bytes(stmt, columnIndex); 

// And now you can access the data 

unsigned sum = 0; 
for (size_t i = 0; i < length; i++) 
    sum += data[i];