* fix segfault on ATTACH MATERIALIZED VIEW
* allow only TEMPORARY TABLEs (not databases or views)
* forbid choosing ENGINE for TEMPORARY tables
* fix segfault on CREATE TABLE t1 AS t2 where t2 is a View
* Log query id in executeQuery; Better type mismatch error; change format in report tool
* Better log query_id
* fix message
* Use c++11 thread_local instaed of gcc's __thread
* lock mutex before notifying waiting thread in sync insertion into distributed [#CLICKHOUSE-3379]
* Cmake: fix build without downloaded submodules (#1379)
* fix
Allow `ATTACH TABLE [db.]name` if the table was previously detached,
an the table structure can be read from disk. This makes reattaching
tables less cumbersome:
```
CREATE TABLE test.t (x UInt8) ENGINE = Null;
DETACH TABLE test.t;
ATTACH TABLE test.t;
```
This allows creation of materialized views without inner tables,
using an existing table for materialized rows instead.
This is useful for cases when you want to detach the materializing
view, but keep the already materialized data readable, especially
when the inner table is replicated.
The built-in clang doesn’t support value() for
`std::experimental::optional`. It however supports
dereference operator, which is basically the
same thing:
```
/clickhouse/dbms/src/DataStreams/NullableAdapterBlockInputStream.cpp:83:67: error: call to unavailable member function 'value':
res.insert({elem.column, elem.type, rename[i].value()});
~~~~~~~~~~^~~~~
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/experimental/optional:547:17: note: candidate function has been explicitly made unavailable
value_type& value()
^
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/include/c++/v1/experimental/optional:539:33: note: candidate function has been explicitly made unavailable
constexpr value_type const& value() const
```
Added a new table engine backed by Apache Kafka,
it allows near real-time ingestion or ETL with
exactly-once semantics.
It doesn’t store any data on disk, so data must
be materialized into a physical table to allow
random access.
Currently it only supports reading, no insertion.
This allows sending notifications to supported
table engines when their dependencies change.
For example, a table can be notified when a
MATERIALIZED VIEW is attached to it.
This is a building block for building pipelines.
