IMP-00020 long column too large for column buffer size (number)Cause: The column buffer is too small. This usually occurs when importing LONG data. Action: Increase the insert buffer size 10,000 bytes at a time (for example). Use this step-by-step approach because a buffer size that is too large may cause a similar problem.
Default: operating system-dependentThe integer specified for BUFFER is the size, in bytes, of the buffer through which data rows are transferred.BUFFER determines the number of rows in the array inserted by Import. The following formula gives an approximation of the buffer size that inserts a given array of rows: buffer_size = rows_in_array * maximum_row_sizeFor tables containing LONG, LOB, BFILE, REF, ROWID, UROWID, or DATE columns, rows are inserted individually. The size of the buffer must be large enough to contain the entire row, except for LOB and LONG columns. If the buffer cannot hold the longest row in a table, Import attempts to allocate a larger buffer.在imp命令中逐步增加buffer参数的大小试试
data rows are transferred.BUFFER determines the number of rows in the array inserted by Import. The
following formula gives an approximation of the buffer size that inserts a given
array of rows:
buffer_size = rows_in_array * maximum_row_sizeFor tables containing LONG, LOB, BFILE, REF, ROWID, UROWID, or DATE
columns, rows are inserted individually. The size of the buffer must be large enough
to contain the entire row, except for LOB and LONG columns. If the buffer cannot
hold the longest row in a table, Import attempts to allocate a larger buffer.在imp命令中逐步增加buffer参数的大小试试