Drop Table functionality in AlsoSQL(JsonServer plugin of Drizzle)

Do you want to drop table just with the help of json. Now you can do that , recently I have added drop table functionality with json_server plugin.

If you check with Drop table syntax in SQL. You can use drop table in various ways:

• Drop Table.
• Drop Table If_exists.
• Drop Temporary Table.

Json Server allows to drop table in first two ways only.

How you can drop a table?

Its really simple, just start drizzled server with json_server plugin enabled.And then send a curl request to drop a table.

Here is a demo version:

• Create a schema name as "json" and a table "test" in drizzle database.
• Now send a HTTP request to drizzle server.

curl -H "Content-Type: application/json" -H "Accept: application/json" -X POST -d '{"query":{"schema_name":"json","table_name":"test"}}' 'http://localhost:8086/json/ddl/table/drop'

• HTTP Response.

{
   "sql_state" : "00000"
}

• Send a HTTP request for "DROP TABLE IF_EXISTS [TABLE_NAME]"

curl -H "Content-Type: application/json" -H "Accept: application/json" -X POST -d '{"query":{"schema_name":"json","table_name":"test","if_exists":"true"}}' 'http://localhost:8086/json/ddl/table/drop'

• Response should be:

{
   "sql_state" : "00000"
}

Drizzle internals doesn't allow identifier::Table to drop a table, they use TableList. So Overload a function with identifier::Table as parameter works for me.

Branch related to this work: lp:~mohyt/drizzle/json_server_table

Beware to say "Treat warning as an error" in new GCC

Are you building your something using Gcc(>=4.6) ?
If yes, then you used be more careful to use "treat warning as an error".
Recently I tried to build zbase over Ubuntu 12.04 2 which uses Gcc (4.6.2) and I faced lots of problem.
And then I moved to Gcc(4.2), everything was too smooth. No error or warnings.

Then I looked into Gcc release details and came across with few important points:

• -Wunused-but-set-variable and -Wunused-but-set-parameter warnings were added. Also the -Wunused-but-set-variable warning is enabled by default by -Wall flag and -Wunused-but-set-parameter by -Wall -Wextra flags.
• Also you may face few linkers problem. I faced a one with jemalloc.

For more about changes have a look here :)

In drizzle , I have to include "config.h" in each file to get rid of this type of error.

Setting Up a Drizzle Development Ubuntu Box

Sometimes we just get bored to figure out dependencies for drizzle development.

Ubuntu have a drizzle-dev package for development purpose. But for me it's not sufficient.

I follow this particular steps for box setup:

• Get Ubuntu 12.04 or whatever you like, install it on virtual box.
• Now after setting up Ubuntu VM-Box. Open terminal and type:
  
  sudo apt-get install bzr drizzle-dev autopoint libboost1.48-all-dev libprotobuf-dev protobuf-compiler uuid-dev libcloog-ppl
• Also you can try apt-get build-dep drizzle
• Now compile source as mention here.

What's new in Json Server ??

As a part of Drizzle , I just started changing the internals of JSON Server with the help of Stewart.
So, what's new ? . That is a big question for this plugin. Last time I did some re-factoring and implemented some new functionalities. Right now I am not focusing on functionality part too much. But yeah, plugin will come up with some new functionalities soon.

Previous version is capable of basic functionality like Insertion, deletion , selection etc. For more details look here. In previous versions , we generate a sql query by parsing json request and then execute that query with the help of Execute API. But Execute API restricts some functionality.

So I just tried to perform sql execution without Execute API. Now we just parse json query and uses parameter with Storage Engine API.

Right now we have two functionalities with such implementation:

• Create Schema
• Drop Schema

If you like to play with this, try out this branch (lp:~mohyt/drizzle/drizzle-json_server) .

How to play with it? , its too simple :

• Start your drizzle server with json plugin enabled (./drizzled/drizzled --plugin-add=json_server)
• Now send a curl request to create schema. For example,

 --exec curl -H "Content-Type: application/json" -H "Accept: application/json" -X POST -d '{"query":{"name":"json"}}' 'http://localhost:8086/json/ddl/schema/create'

• And , to drop a schema , try this ,  

--exec curl -H "Content-Type: application/json" -H "Accept: application/json" -X POST -d '{"query":{"name":"json"}}' 'http://localhost:8086/json/ddl/schema/drop'

Comments are most welcome :)