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Viewing changes to storage/innobase/include/row0ext.ic

  • Committer: Monty Taylor
  • Date: 2009-03-25 21:06:47 UTC
  • mto: This revision was merged to the branch mainline in revision 964.
  • Revision ID: mordred@inaugust.com-20090325210647-7j1tm98gvct3jxsu
Removed legacy_db_type.

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storage/innobase/include/row0ext.ic
 
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/*****************************************************************************
 
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Copyright (c) 2006, 2009, Innobase Oy. All Rights Reserved.
 
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This program is free software; you can redistribute it and/or modify it under
 
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the terms of the GNU General Public License as published by the Free Software
 
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Foundation; version 2 of the License.
 
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This program is distributed in the hope that it will be useful, but WITHOUT
 
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 
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FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 
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You should have received a copy of the GNU General Public License along with
 
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this program; if not, write to the Free Software Foundation, Inc., 59 Temple
 
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Place, Suite 330, Boston, MA 02111-1307 USA
 
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*****************************************************************************/
 
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/******************************************************
 
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Caching of externally stored column prefixes
 
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Created September 2006 Marko Makela
 
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*******************************************************/
 
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#include "rem0types.h"
 
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#include "btr0types.h"
 
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/************************************************************************
 
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Looks up a column prefix of an externally stored column. */
 
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UNIV_INLINE
 
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const byte*
 
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row_ext_lookup_ith(
 
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/*===============*/
 
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                                        /* out: column prefix, or NULL if
 
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                                        the column is not stored externally,
 
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                                        or pointer to field_ref_zero
 
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                                        if the BLOB pointer is unset */
 
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        const row_ext_t*        ext,    /* in/out: column prefix cache */
 
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        ulint                   i,      /* in: index of ext->ext[] */
 
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        ulint*                  len)    /* out: length of prefix, in bytes,
 
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                                        at most REC_MAX_INDEX_COL_LEN */
 
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{
 
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        ut_ad(ext);
 
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        ut_ad(len);
 
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        ut_ad(i < ext->n_ext);
 
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        *len = ext->len[i];
 
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        if (UNIV_UNLIKELY(*len == 0)) {
 
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                /* The BLOB could not be fetched to the cache. */
 
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                return(field_ref_zero);
 
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        } else {
 
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                return(ext->buf + i * REC_MAX_INDEX_COL_LEN);
 
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        }
 
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}
 
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/************************************************************************
 
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Looks up a column prefix of an externally stored column. */
 
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UNIV_INLINE
 
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const byte*
 
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row_ext_lookup(
 
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/*===========*/
 
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                                        /* out: column prefix, or NULL if
 
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                                        the column is not stored externally,
 
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                                        or pointer to field_ref_zero
 
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                                        if the BLOB pointer is unset */
 
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        const row_ext_t*        ext,    /* in: column prefix cache */
 
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        ulint                   col,    /* in: column number in the InnoDB
 
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                                        table object, as reported by
 
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                                        dict_col_get_no(); NOT relative to the
 
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                                        records in the clustered index */
 
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        ulint*                  len)    /* out: length of prefix, in bytes,
 
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                                        at most REC_MAX_INDEX_COL_LEN */
 
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{
 
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        ulint   i;
 
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        ut_ad(ext);
 
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        ut_ad(len);
 
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        for (i = 0; i < ext->n_ext; i++) {
 
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                if (col == ext->ext[i]) {
 
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                        return(row_ext_lookup_ith(ext, i, len));
 
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                }
 
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        }
 
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        return(NULL);
 
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}