MDEV-23497 Make ROW_FORMAT=COMPRESSED read-only by default

Let us introduce the parameter innodb_read_only_compressed
that is ON by default, making any ROW_FORMAT=COMPRESSED tables
read-only.

I developed the ROW_FORMAT=COMPRESSED format based on
Heikki Tuuri's rough design between 2005 and 2008. It might
have been a good idea back then, but no proper benchmarks were
ever run to validate the design or the implementation.

The format has been more or less obsolete for years.
It limits innodb_page_size to 16384 bytes (the default),
and instant ALTER TABLE is not supported.

This is the first step towards deprecating and removing
write support for ROW_FORMAT=COMPRESSED tables.

1 files changed, 0 insertions, 32 deletions

diff --git a/mysql-test/suite/innodb/t/innodb_blob_truncate.test b/mysql-test/suite/innodb/t/innodb_blob_truncate.test
deleted file mode 100644
index 3e54ec80e2b..00000000000
--- a/mysql-test/suite/innodb/t/innodb_blob_truncate.test
+++ /dev/null
@@ -1,32 +0,0 @@
---source include/have_innodb.inc
---source include/have_innodb_16k.inc
-
-create table t1(a blob) engine=innodb key_block_size=8;
-delimiter //;
-create function generate_blob()
-  returns varchar(20000)
-  begin
-    declare x varchar(20000) default '';
-    declare i int default 500;
-    while i > 0 do
-      set x = concat(sha1(i), x);
-      set i = i - 1;
-    end while;
-  return x;
-end //
-delimiter ;//
-insert into t1 select generate_blob();
-let $x = `select 20000 - length(a) from t1`;
-if ($x) {
-  echo Blob is truncated by $x bytes.;
-  die It must have been 20000 bytes.;
-}
-truncate t1;
-insert into t1 select generate_blob();
-let $x = `select 20000 - length(a) from t1`;
-if ($x) {
-  echo Blob is truncated by $x bytes.;
-  die It must have been 20000 bytes.;
-}
-drop table t1;
-drop function generate_blob;