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/******************************************************
Row versions
(c) 1997 Innobase Oy
Created 2/6/1997 Heikki Tuuri
*******************************************************/
#include "row0row.h"
#include "dict0dict.h"
#include "read0read.h"
#include "page0page.h"
#include "log0recv.h"
/*************************************************************************
Fetches the trx id of a clustered index record or version. */
UNIV_INLINE
dulint
row_vers_get_trx_id(
/*================*/
/* out: trx id or ut_dulint_zero if the
clustered index record not found */
rec_t* rec, /* in: clustered index record, or an old
version of it */
dict_table_t* table) /* in: table */
{
return(row_get_rec_trx_id(rec, dict_table_get_first_index(table)));
}
/*************************************************************************
Checks if a consistent read can be performed immediately on the index
record, or if an older version is needed. */
UNIV_INLINE
ibool
row_vers_clust_rec_sees_older(
/*==========================*/
/* out: FALSE if can read immediately */
rec_t* rec, /* in: record which should be read or passed
over by a read cursor */
dict_index_t* index, /* in: clustered index */
read_view_t* view) /* in: read view */
{
ut_ad(index->type & DICT_CLUSTERED);
if (read_view_sees_trx_id(view, row_get_rec_trx_id(rec, index))) {
return(FALSE);
}
return(TRUE);
}
/*************************************************************************
Checks if a secondary index record can be read immediately by a consistent
read, or if an older version may be needed. To be sure, we will have to
look in the clustered index. */
UNIV_INLINE
ibool
row_vers_sec_rec_may_see_older(
/*===========================*/
/* out: FALSE if can be read immediately */
rec_t* rec, /* in: record which should be read or passed */
dict_index_t* index, /* in: secondary index */
read_view_t* view) /* in: read view */
{
page_t* page;
ut_ad(!(index->type & DICT_CLUSTERED));
page = buf_frame_align(rec);
if ((ut_dulint_cmp(page_get_max_trx_id(page), view->up_limit_id) >= 0)
|| recv_recovery_is_on()) {
/* It may be that the record was inserted or modified by a
transaction the view should not see: we have to look in the
clustered index */
return(TRUE);
}
return(FALSE);
}
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