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diff --git a/storage/innobase/include/btr0cur.inl b/storage/innobase/include/btr0cur.inl
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+/*****************************************************************************
+
+Copyright (c) 1994, 2015, Oracle and/or its affiliates. All Rights Reserved.
+Copyright (c) 2018, 2021, MariaDB Corporation.
+
+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 the Free Software
+Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+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 Street, Fifth Floor, Boston, MA 02110-1335 USA
+
+*****************************************************************************/
+
+/**************************************************//**
+@file include/btr0cur.ic
+The index tree cursor
+
+Created 10/16/1994 Heikki Tuuri
+*******************************************************/
+
+#include "btr0btr.h"
+
+#ifdef UNIV_DEBUG
+# define LIMIT_OPTIMISTIC_INSERT_DEBUG(NREC, CODE)\
+if (btr_cur_limit_optimistic_insert_debug > 1\
+    && (NREC) >= btr_cur_limit_optimistic_insert_debug) {\
+        CODE;\
+}
+#else
+# define LIMIT_OPTIMISTIC_INSERT_DEBUG(NREC, CODE)
+#endif /* UNIV_DEBUG */
+
+/*********************************************************//**
+Returns the compressed page on which the tree cursor is positioned.
+@return pointer to compressed page, or NULL if the page is not compressed */
+UNIV_INLINE
+page_zip_des_t*
+btr_cur_get_page_zip(
+/*=================*/
+	btr_cur_t*	cursor)	/*!< in: tree cursor */
+{
+	return(buf_block_get_page_zip(btr_cur_get_block(cursor)));
+}
+
+/*********************************************************//**
+Returns the page of a tree cursor.
+@return pointer to page */
+UNIV_INLINE
+page_t*
+btr_cur_get_page(
+/*=============*/
+	btr_cur_t*	cursor)	/*!< in: tree cursor */
+{
+	return(page_align(page_cur_get_rec(&(cursor->page_cur))));
+}
+
+/*********************************************************//**
+Positions a tree cursor at a given record. */
+UNIV_INLINE
+void
+btr_cur_position(
+/*=============*/
+	dict_index_t*	index,	/*!< in: index */
+	rec_t*		rec,	/*!< in: record in tree */
+	buf_block_t*	block,	/*!< in: buffer block of rec */
+	btr_cur_t*	cursor)	/*!< out: cursor */
+{
+	page_cur_position(rec, block, btr_cur_get_page_cur(cursor));
+	cursor->index = index;
+}
+
+/*********************************************************************//**
+Checks if compressing an index page where a btr cursor is placed makes
+sense.
+@return TRUE if compression is recommended */
+UNIV_INLINE
+ibool
+btr_cur_compress_recommendation(
+/*============================*/
+	btr_cur_t*	cursor,	/*!< in: btr cursor */
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	const page_t*	page;
+
+	ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor),
+					 MTR_MEMO_PAGE_X_FIX));
+
+	page = btr_cur_get_page(cursor);
+
+	LIMIT_OPTIMISTIC_INSERT_DEBUG(page_get_n_recs(page) * 2U,
+				      return(FALSE));
+
+	if (!page_has_siblings(page)
+	    || page_get_data_size(page)
+	    < BTR_CUR_PAGE_COMPRESS_LIMIT(cursor->index)) {
+
+		/* The page fillfactor has dropped below a predefined
+		minimum value OR the level in the B-tree contains just
+		one page: we recommend compression if this is not the
+		root page. */
+
+		return cursor->index->page
+			!= btr_cur_get_block(cursor)->page.id().page_no();
+	}
+
+	return(FALSE);
+}
+
+/*********************************************************************//**
+Checks if the record on which the cursor is placed can be deleted without
+making tree compression necessary (or, recommended).
+@return TRUE if can be deleted without recommended compression */
+UNIV_INLINE
+ibool
+btr_cur_can_delete_without_compress(
+/*================================*/
+	btr_cur_t*	cursor,	/*!< in: btr cursor */
+	ulint		rec_size,/*!< in: rec_get_size(btr_cur_get_rec(cursor))*/
+	mtr_t*		mtr)	/*!< in: mtr */
+{
+	page_t*		page;
+
+	ut_ad(mtr->memo_contains_flagged(btr_cur_get_block(cursor),
+					 MTR_MEMO_PAGE_X_FIX));
+
+	page = btr_cur_get_page(cursor);
+
+	if (!page_has_siblings(page) || page_get_n_recs(page) < 2
+	    || page_get_data_size(page) - rec_size
+	    < BTR_CUR_PAGE_COMPRESS_LIMIT(cursor->index)) {
+
+		/* The page fillfactor will drop below a predefined
+		minimum value, OR the level in the B-tree contains just
+		one page, OR the page will become empty: we recommend
+		compression if this is not the root page. */
+
+		return cursor->index->page
+			== btr_cur_get_block(cursor)->page.id().page_no();
+	}
+
+	return(TRUE);
+}
+
+/*******************************************************************//**
+Determine if an operation on off-page columns is an update.
+@return TRUE if op != BTR_STORE_INSERT */
+UNIV_INLINE
+ibool
+btr_blob_op_is_update(
+/*==================*/
+	enum blob_op	op)	/*!< in: operation */
+{
+	switch (op) {
+	case BTR_STORE_INSERT:
+	case BTR_STORE_INSERT_BULK:
+		return(FALSE);
+	case BTR_STORE_INSERT_UPDATE:
+	case BTR_STORE_UPDATE:
+		return(TRUE);
+	}
+
+	ut_ad(0);
+	return(FALSE);
+}