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authorunknown <monty@donna.mysql.com>2001-02-17 14:19:19 +0200
committerunknown <monty@donna.mysql.com>2001-02-17 14:19:19 +0200
commit2662b59306ef0cd495fa6e2edf7129e58a11393a (patch)
treebfe39951a73e906579ab819bf5198ad8f3a64a36 /innobase/include/read0read.h
parent66de55a56bdcf2f7a9c0c4f8e19b3e761475e202 (diff)
downloadmariadb-git-2662b59306ef0cd495fa6e2edf7129e58a11393a.tar.gz
Added Innobase to source distribution
Docs/manual.texi: Added Innobase documentation configure.in: Incremented version include/my_base.h: Added option for Innobase myisam/mi_check.c: cleanup mysql-test/t/bdb.test: cleanup mysql-test/t/innobase.test: Extended with new tests from bdb.test mysql-test/t/merge.test: Added test of SHOW create mysys/my_init.c: Fix for UNIXWARE 7 scripts/mysql_install_db.sh: Always write how to start mysqld scripts/safe_mysqld.sh: Fixed type sql/ha_innobase.cc: Update to new version sql/ha_innobase.h: Update to new version sql/handler.h: Added 'update_table_comment()' and 'append_create_info()' sql/sql_delete.cc: Fixes for Innobase sql/sql_select.cc: Fixes for Innobase sql/sql_show.cc: Append create information (for MERGE tables) sql/sql_update.cc: Fixes for Innobase
Diffstat (limited to 'innobase/include/read0read.h')
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diff --git a/innobase/include/read0read.h b/innobase/include/read0read.h
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+++ b/innobase/include/read0read.h
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+/******************************************************
+Cursor read
+
+(c) 1997 Innobase Oy
+
+Created 2/16/1997 Heikki Tuuri
+*******************************************************/
+
+#ifndef read0read_h
+#define read0read_h
+
+#include "univ.i"
+
+
+#include "ut0byte.h"
+#include "ut0lst.h"
+#include "trx0trx.h"
+#include "read0types.h"
+
+/*************************************************************************
+Opens a read view where exactly the transactions serialized before this
+point in time are seen in the view. */
+
+read_view_t*
+read_view_open_now(
+/*===============*/
+ /* out, own: read view struct */
+ trx_t* cr_trx, /* in: creating transaction, or NULL */
+ mem_heap_t* heap); /* in: memory heap from which allocated */
+/*************************************************************************
+Makes a copy of the oldest existing read view, or opens a new. The view
+must be closed with ..._close. */
+
+read_view_t*
+read_view_oldest_copy_or_open_new(
+/*==============================*/
+ /* out, own: read view struct */
+ trx_t* cr_trx, /* in: creating transaction, or NULL */
+ mem_heap_t* heap); /* in: memory heap from which allocated */
+/*************************************************************************
+Closes a read view. */
+
+void
+read_view_close(
+/*============*/
+ read_view_t* view); /* in: read view */
+/*************************************************************************
+Checks if a read view sees the specified transaction. */
+UNIV_INLINE
+ibool
+read_view_sees_trx_id(
+/*==================*/
+ /* out: TRUE if sees */
+ read_view_t* view, /* in: read view */
+ dulint trx_id); /* in: trx id */
+
+
+/* Read view lists the trx ids of those transactions for which a consistent
+read should not see the modifications to the database. */
+
+struct read_view_struct{
+ ibool can_be_too_old; /* TRUE if the system has had to purge old
+ versions which this read view should be able
+ to access: the read view can bump into the
+ DB_MISSING_HISTORY error */
+ dulint low_limit_no; /* The view does not need to see the undo
+ logs for transactions whose transaction number
+ is strictly smaller (<) than this value: they
+ can be removed in purge if not needed by other
+ views */
+ dulint low_limit_id; /* The read should not see any transaction
+ with trx id >= this value */
+ dulint up_limit_id; /* The read should see all trx ids which
+ are strictly smaller (<) than this value */
+ ulint n_trx_ids; /* Number of cells in the trx_ids array */
+ dulint* trx_ids; /* Additional trx ids which the read should
+ not see: typically, these are the active
+ transactions at the time when the read is
+ serialized, except the reading transaction
+ itself; the trx ids in this array are in a
+ descending order */
+ trx_t* creator; /* Pointer to the creating transaction, or
+ NULL if used in purge */
+ UT_LIST_NODE_T(read_view_t) view_list;
+ /* List of read views in trx_sys */
+};
+
+#ifndef UNIV_NONINL
+#include "read0read.ic"
+#endif
+
+#endif