branches/zip: Make TRUNCATE TABLE recreate single-table tablespaces.

dict_truncate_index_tree(): Add the parameter space for specifying the
new tablespace identifier of a single-table tablespace that has been
recreated.  When SYS_INDEXES.PAGE_NO == FIL_NULL, do not abort but
create the index tree.

fil_discard_tablespace(): Pass the return code from fil_delete_tablespace().

row_truncate_table_for_mysql(): Attempt to discard and recreate
single-table tablespaces.  Reassign the tablespace identifier both in
the data dictionary (SYS_TABLES and SYS_INDEXES) and in the data
dictionary cache.

dict/dict0crea.c

@@ -705,6 +705,9 @@ dict_truncate_index_tree(
 				/* out: new root page number, or
 				FIL_NULL on failure */
 	dict_table_t*	table,	/* in: the table the index belongs to */
+	ulint		space,	/* in: 0=truncate,
+				nonzero=create the index tree in the
+				given tablespace */
 	btr_pcur_t*	pcur,	/* in/out: persistent cursor pointing to
 				record in the clustered index of
 				SYS_INDEXES table. The cursor may be
@@ -714,14 +717,13 @@ dict_truncate_index_tree(
 				committed and restarted in this call. */
 {
 	ulint		root_page_no;
-	ulint		space;
+	ibool		drop = !space;
 	ulint		zip_size;
 	ulint		type;
 	dulint		index_id;
 	rec_t*		rec;
 	const byte*	ptr;
 	ulint		len;
-	ulint		comp;
 	dict_index_t*	index;
 
 	ut_ad(mutex_own(&(dict_sys->mutex)));
@@ -733,13 +735,13 @@ dict_truncate_index_tree(
 
 	root_page_no = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);
 
-	if (root_page_no == FIL_NULL) {
+	if (drop && root_page_no == FIL_NULL) {
 		/* The tree has been freed. */
 
 		ut_print_timestamp(stderr);
 		fprintf(stderr, "  InnoDB: Trying to TRUNCATE"
 			" a missing index of table %s!\n", table->name);
-		return(FIL_NULL);
+		drop = FALSE;
 	}
 
 	ptr = rec_get_nth_field_old(rec,
@@ -747,7 +749,10 @@ dict_truncate_index_tree(
 
 	ut_ad(len == 4);
 
-	space = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);
+	if (drop) {
+		space = mtr_read_ulint(ptr, MLOG_4BYTES, mtr);
+	}
+
 	zip_size = fil_space_get_zip_size(space);
 
 	if (UNIV_UNLIKELY(zip_size == ULINT_UNDEFINED)) {
@@ -769,6 +774,11 @@ dict_truncate_index_tree(
 	ut_ad(len == 8);
 	index_id = mach_read_from_8(ptr);
 
+	if (!drop) {
+
+		goto create;
+	}
+
 	/* We free all the pages but the root page first; this operation
 	may span several mini-transactions */
 
@@ -779,10 +789,10 @@ dict_truncate_index_tree(
 	appropriate field in the SYS_INDEXES record: this mini-transaction
 	marks the B-tree totally truncated */
 
-	comp = page_is_comp(btr_page_get(space, zip_size, root_page_no,
-					 RW_X_LATCH, mtr));
+	btr_page_get(space, zip_size, root_page_no, RW_X_LATCH, mtr);
 
 	btr_free_root(space, zip_size, root_page_no, mtr);
+create:
 	/* We will temporarily write FIL_NULL to the PAGE_NO field
 	in SYS_INDEXES, so that the database will not get into an
 	inconsistent state in case it crashes between the mtr_commit()

fil/fil0fil.c

@@ -2293,7 +2293,7 @@ fil_discard_tablespace(
 
 	ibuf_delete_for_discarded_space(id);
 
-	return(TRUE);
+	return(success);
 }
 
 /***********************************************************************

include/dict0crea.h

@@ -62,6 +62,9 @@ dict_truncate_index_tree(
 				/* out: new root page number, or
 				FIL_NULL on failure */
 	dict_table_t*	table,	/* in: the table the index belongs to */
+	ulint		space,	/* in: 0=truncate,
+				nonzero=create the index tree in the
+				given tablespace */
 	btr_pcur_t*	pcur,	/* in/out: persistent cursor pointing to
 				record in the clustered index of
 				SYS_INDEXES table. The cursor may be

row/row0mysql.c

@@ -2665,6 +2665,7 @@ row_truncate_table_for_mysql(
 	btr_pcur_t	pcur;
 	mtr_t		mtr;
 	dulint		new_id;
+	ulint		recreate_space = 0;
 	pars_info_t*	info = NULL;
 
 	/* How do we prevent crashes caused by ongoing operations on
@@ -2689,17 +2690,23 @@ row_truncate_table_for_mysql(
 	reallocated, the allocator will remove the ibuf entries for
 	it.
 
-	TODO: when we truncate *.ibd files (analogous to DISCARD
-	TABLESPACE), we will have to remove we remove all entries for
-	the table in the insert buffer tree!
+	When we truncate *.ibd files by recreating them (analogous to
+	DISCARD TABLESPACE), we remove all entries for the table in the
+	insert buffer tree.  This is not strictly necessary, because
+	in 6) we will assign a new tablespace identifier, but we can
+	free up some space in the system tablespace.
 
 	4) Linear readahead and random readahead: we use the same
-	method as in 3) to discard ongoing operations. (This will only
-	be relevant for TRUNCATE TABLE by DISCARD TABLESPACE.)
+	method as in 3) to discard ongoing operations. (This is only
+	relevant for TRUNCATE TABLE by DISCARD TABLESPACE.)
 
 	5) FOREIGN KEY operations: if
 	table->n_foreign_key_checks_running > 0, we do not allow the
-	TRUNCATE. We also reserve the data dictionary latch. */
+	TRUNCATE. We also reserve the data dictionary latch.
+
+	6) Crash recovery: To prevent the application of pre-truncation
+	redo log records on the truncated tablespace, we will assign
+	a new tablespace identifier to the truncated tablespace. */
 
 	ut_ad(trx->mysql_thread_id == os_thread_get_curr_id());
 	ut_ad(table);
@@ -2790,6 +2797,51 @@ row_truncate_table_for_mysql(
 
 	trx->table_id = table->id;
 
+	if (table->space && !table->dir_path_of_temp_table) {
+		/* Discard and create the single-table tablespace. */
+		ulint	space	= table->space;
+		ulint	zip_size= fil_space_get_zip_size(space);
+
+		if (zip_size != ULINT_UNDEFINED
+		    && fil_discard_tablespace(space)) {
+
+			dict_index_t*	index;
+
+			space = 0;
+
+			if (fil_create_new_single_table_tablespace(
+				    &space, table->name, FALSE, zip_size,
+				    FIL_IBD_FILE_INITIAL_SIZE) != DB_SUCCESS) {
+				ut_print_timestamp(stderr);
+				fprintf(stderr,
+					"  InnoDB: TRUNCATE TABLE %s failed to"
+					" create a new tablespace\n",
+					table->name);
+				table->ibd_file_missing = 1;
+				err = DB_ERROR;
+				goto funct_exit;
+			}
+
+			recreate_space = space;
+
+			/* Replace the space_id in the data dictionary cache.
+			The persisent data dictionary (SYS_TABLES.SPACE
+			and SYS_INDEXES.SPACE) are updated later in this
+			function. */
+			table->space = space;
+			index = dict_table_get_first_index(table);
+			do {
+				index->space = space;
+				index = dict_table_get_next_index(index);
+			} while (index);
+
+			mtr_start(&mtr);
+			fsp_header_init(space,
+					FIL_IBD_FILE_INITIAL_SIZE, &mtr);
+			mtr_commit(&mtr);
+		}
+	}
+
 	/* scan SYS_INDEXES for all indexes of the table */
 	heap = mem_heap_create(800);
 
@@ -2834,7 +2886,8 @@ row_truncate_table_for_mysql(
 
 		/* This call may commit and restart mtr
 		and reposition pcur. */
-		root_page_no = dict_truncate_index_tree(table, &pcur, &mtr);
+		root_page_no = dict_truncate_index_tree(table, recreate_space,
+							&pcur, &mtr);
 
 		rec = btr_pcur_get_rec(&pcur);
 
@@ -2866,17 +2919,20 @@ row_truncate_table_for_mysql(
 
 	info = pars_info_create();
 
+	pars_info_add_int4_literal(info, "space", (lint) table->space);
 	pars_info_add_dulint_literal(info, "old_id", table->id);
 	pars_info_add_dulint_literal(info, "new_id", new_id);
 
 	err = que_eval_sql(info,
 			   "PROCEDURE RENUMBER_TABLESPACE_PROC () IS\n"
 			   "BEGIN\n"
-			   "UPDATE SYS_TABLES SET ID = :new_id\n"
+			   "UPDATE SYS_TABLES"
+			   " SET ID = :new_id, SPACE = :space\n"
 			   " WHERE ID = :old_id;\n"
 			   "UPDATE SYS_COLUMNS SET TABLE_ID = :new_id\n"
 			   " WHERE TABLE_ID = :old_id;\n"
-			   "UPDATE SYS_INDEXES SET TABLE_ID = :new_id\n"
+			   "UPDATE SYS_INDEXES"
+			   " SET TABLE_ID = :new_id, SPACE = :space\n"
 			   " WHERE TABLE_ID = :old_id;\n"
 			   "COMMIT WORK;\n"
 			   "END;\n"