SCQL Manual

SCQL Data Types

SCQL supports frequently-used data types, as illustrated in the following table.

Data Type	Alias	Description
integer	int, long, int64
float	double	both storage and computation are done in type float32
string	str
datetime		not supported yet, coming soon
timestamp		not supported yet, coming soon

SCQL Statements

SCQL is compatible with most MySQL syntax, which makes it easy to use. For syntax differences between SCQL and MySQL, please read MySQL Compatibility.

CREATE/DROP USER Statement

CREATE USER [IF NOT EXISTS] user party_code_option IDENTIFIED BY 'auth_string'

party_code_option:
    PARTY_CODE party_code

DROP USER [IF EXISTS] user

Examples:

-- create an user named alice,
-- with password `alice123`,
-- belongs to party `party_alice`
CREATE USER alice PARTY_CODE "party_alice" IDENTIFIED BY "alice123";

-- drop user alice
DROP USER alice;

CREATE/DROP DATABASE Statement

CREATE DATABASE [IF NOT EXISTS] database;

DROP DATABASE [IF EXISTS] database;

Examples:

-- create db `db_test`
CREATE DATABASE db_test;

-- drop db `db_test`
DROP DATABASE db_test;

CREATE/DROP TABLE Statement

CREATE TABLE [IF NOT EXISTS] tbl_name TID [=] value

DROP TABLE [IF EXISTS] tbl_name

Note

Create table here means mapping ‘tbl_name’ to the existing physic table, which is specified by ‘TID’ and located on the relevant parties. In SCQL, user runs queries on virtual table, which helps simplify privilege control and usage.

Examples:

-- create a table `ta` in database `db_test`,
-- the new table references the table with TID = `table-id` in GRM,
-- SCQL would fetch the table schema from GRM with given `TID`.
CREATE TABLE db_test.ta TID="table-id";

DROP TABLE db_test.ta;

GRANT/REVOKE Statement

GRANT
extend_priv_type [(column_list)]
  [, extend_priv_type[(column_list)]] ...
ON priv_level
TO user

REVOKE [IF EXISTS]
extend_priv_type [(column_list)]
  [, extend_priv_type[(column_list)]] ...
ON priv_level
FROM user

extend_priv_type:
    priv_type | SELECT [CCL level]

Examples:

-- GRANT privileges
GRANT CREATE VIEW on db.* to alice;
GRANT SHOW, DESCRIBE ON db.* TO 'someuser'@'somehost';
-- GRANT CCL
GRANT SELECT PLAINTEXT_AFTER_JOIN(column) on db.table to user;
-- REVOKE CCL
REVOKE SELECT PLAINTEXT_AFTER_AGGREGATE(column) ON db.table FROM user;

SHOW/DESCRIBE Statement

SHOW DATABASES;

SHOW TABLES;

SHOW GRANTS on <db_name> FOR <user>;

DESCRIBE <db_name>.<table_name>;

SELECT Statement

SELECT [DISTINCT] select_expr [, select_expr] ...
[FROM table_reference]
[WHERE where_condition]
[GROUP BY column]

select_expr:
    col_reference [AS alias]

col_reference:
    column
| agg_function(column)

column:
    *
| db_name.tbl_name.col_name field_as_name_opt
| alias.col_name field_as_name_opt
| expression field_as_name_opt

field_as_name_opt:
    ""
| field_as_name

field_as_name:
    identifier
| "AS" identifier

table_reference:
    table_factor
| join_table
| union_table

table_factor:
    db_name.tbl_name [[AS] alias]

join_table:
    table_reference [INNER] JOIN table_factor [join_specification]

union_table:
    select_expr
    | UNION [ALL] union_table

join_specification:
    ON search_condition

expression:
    expression "SUPPORTED_OP" expression
    | "NOT" expression
    | predicate_expr

predicate_expr:
    column InOrNotOp '(' expression_list ')'
    | column InOrNotOp sub_select
    | column

sub_select:
    '(' select_stmt ')'

Limitation:

• JOIN only supports

  • INNER JOIN

Functions and Operators

Todo

this part is not ready, please check later