diff options
Diffstat (limited to 'sql/field.h')
| -rw-r--r-- | sql/field.h | 24 |
1 files changed, 21 insertions, 3 deletions
diff --git a/sql/field.h b/sql/field.h index f3f0ff193c7..933bbe2c018 100644 --- a/sql/field.h +++ b/sql/field.h @@ -1,5 +1,5 @@ -/* Copyright (c) 2000, 2010 Oracle and/or its affiliates. - Copyright (c) 2009-2011 Monty Program Ab +/* Copyright (c) 2000, 2011, Oracle and/or its affiliates. + Copyright (c) 2008-2011 Monty Program Ab This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -12,7 +12,8 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +*/ #include "my_compare.h" /* for clr_rec_bits */ @@ -2239,6 +2240,23 @@ public: uchar *from_null_ptr,*to_null_ptr; bool *null_row; uint from_bit,to_bit; + /** + Number of bytes in the fields pointed to by 'from_ptr' and + 'to_ptr'. Usually this is the number of bytes that are copied from + 'from_ptr' to 'to_ptr'. + + For variable-length fields (VARCHAR), the first byte(s) describe + the actual length of the text. For VARCHARs with length + < 256 there is 1 length byte + >= 256 there is 2 length bytes + Thus, if from_field is VARCHAR(10), from_length (and in most cases + to_length) is 11. For VARCHAR(1024), the length is 1026. @see + Field_varstring::length_bytes + + Note that for VARCHARs, do_copy() will be do_varstring*() which + only copies the length-bytes (1 or 2) + the actual length of the + text instead of from/to_length bytes. @see get_copy_func() + */ uint from_length,to_length; Field *from_field,*to_field; String tmp; // For items |