触发器语言说明

触发器有定时触发、动作触发两种类型

创建触发器的语法

CREATE OR REPLACE TRIGGER name ON 类名
  属性列表
BEGIN
    代码块
END

删除触发器的语法

# 删除一个触发器的语法
# 若name为*或空，将删除该类下所有的触发器
DROP TRIGGER name ON 类名

#删除一组触发器的语法
DROP TRIGGER ON GROUP 组名

修改触发器的语法

# 允许修改的属性为 STATUS，PRIORITY，GROUP
ALTER  TRIGGER  ON  GROUP  groupname   SET  [STATUS/PRIORITY] =  xxx 
ALTER  TRIGGER  name ON classname  SET [STATUS/PRIORITY/GROUP] =  xxx, ...

定时触发类型触发器的属性

示例

CREATE TRIGGER  test  ON  alert_status
SCHEDULE    EVERY  1  MINUTE
COMMENT        '触发器实例' 
GROUP        network
PRIORITY    1
WHEN        SEVERITY = 2
BIND        id, msg, type AS myvar
STATUS        enable
BEGIN
    for _, v in pair(myvar) do
        log.info("id: "..v.id .. " msg: "..v.msg .." type: ".. tostring(v.type) )
    end
END

动作触发类型触发器的属性

示例

CREATE TRIGGER  tes2t  ON  alert_status
COMMENT        '触发器实例2' 
GROUP        network
PRIORITY    1
SCHEDULE    AFTER  INSERT
STATUS        enable
BEGIN
    log.info("id: "..this.id .. " msg: "..this.msg .." type: ".. tostring(this.type) )
END

全局变量(Global variable)

• this

  table

  触发对象的信息

• old

  table

  触发对象的未修改前信息

• ACTION

  string

  触发对象的动作: INSERT UPDATE DELETE``onconflict

• DATACHANGE

  bool

  是否发送类数据变化事件

函数(Functions)

• strings

  -- split: Split string
  -- params: <s string>, <sep string>
  -- return: <result table>
  local ret = strings.split('a,b,c', ',')
  
  -- replace: Replace string
  -- params: <s string>, <old string>, <new string>, <n int>
  -- return: <result table>
  local ret = strings.replace('Aaaa', 'a', 'A', -1) -- -1: all
  
  -- trim: Trim string space
  -- params: <s string>
  -- return: <result table>
  local ret = strings.trim('Aaaa')
  
  -- join: Join table to string
  -- params: <a table>, <sep string>
  -- return: <result table>
  local ret = strings.join({'a', 'b', 'c'}, ',')
  
  -- fields: Fields splits the string
  -- params: <s string>
  -- return: <result table>
  local ret = strings.fields('A  B C    D')
  

• time

  -- parse: Parse a time string into a number
  -- params: <layout string>, <time string>
  -- return: <time number>
  -- layout: 
      -- yyyy   (year)
      -- MM     (month)
      -- dd     (day)
      -- HH     (24hour)
      -- mm     (minute)
      -- ss     (second)
      -- SSS    (millinseconds)
      -- month  (month English abbreviations)
      -- week   (week English abbreviations)
      -- %y     (year)
      -- %M     (month)
      -- %d     (day)
      -- %H     (hour)
      -- %m     (minute)
      -- %s     (second)
  local ret = time.parse('yyyy-MM-dd HH:mm:ss.SSS', '2016-04-07 15:22:33.666')
  

• log

  -- trace: Print trace message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.trace('Hello', 123)
  
  -- debug: Print debug message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.debug('Hello', 123)
  
  -- info: Print info message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.info('Hello', 123)
  
  -- warn: Print warn message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.warn('Hello', 123)
  
  -- error: Print error message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.error('Hello', 123)
  
  -- fatal: Print fatal message
  -- params: <v1 value>, <v2 value>...
  -- return: None
  log.fatal('Hello', 123)
  

• odb

  -- mql: MQL access ODB
  -- params: <mql statement>
  -- return: <result format: {data:[{}, {}...], meta:{}}>
  local ret = odb.mql('select id from /matrix/test')
  
  -- mql: Search access ODB
  -- params: <search statement>
  -- return: <result format: {data:[{}, {}...], meta:{}}>
  local ret = odb.search('wecise | print id | top 1')
  
  -- getid: Get object id by object table
  -- params: <object table>
  -- return: <id string>
  local id = odb.getid({column0='mxsvr1', class='/matrix/test'})
  

• appcontext

  -- rawget: Get raw cache, key-value mode
  -- params: <key string>
  -- return: <value string>
  local id = appcontext.rawget('testkey')
  
  -- rawset: Set raw cache, key-value mode
  -- params: <key string>, <value string>, <ttl second number>
  -- return: None
  appcontext.rawset('testkey', 'testvalue', 120)
  
  -- create: Create collection cache, collection mode
  -- params: <collection name string>, <value table>, <ttl second number>
  -- return: <id string>
  local id = appcontext.create('zoo', {name='monkey', room=1}, 120)
  
  -- getall: Get collection by condition
  -- params: <collection name string>, <query condition string>
  -- return: <result table>
  -- where: Query logic expression
  --        ||
  --        &&
  --        = != > < >= <= ~= !~= is isnot contains
  --        + -
  --        * / %
  --        ^
  --        ( )
  local list = appcontext.getall("zoo", "room == 1")
  
  -- getfirst: Get the first data of the collection
  -- params: <collection name string>
  -- return: <result table>
  local ret = appcontext.getfirst('zoo')
  
  -- getlast: Get the last data of the collection
  -- params: <collection name string>
  -- return: <result table>
  local ret = appcontext.getlast('zoo')
  
  -- get: Get data of the collection by id
  -- params: <collection name string>, <id string>
  -- return: <result table>
  local ret = appcontext.get('zoo', 'e898853a-74ee-11e8-941c-9eb6d01c8f95')
  
  -- update: Update data of the collection by id
  -- params: <collection name string>, <id string>, <value table>, <ttl number>
  -- return: None
  appcontext.update('zoo', 'e898853a-74ee-11e8-941c-9eb6d01c8f95', {name='monkey', room=2}, 120)
  
  -- deleteall: Delete collection all data
  -- params: <collection name string>
  -- return: None
  appcontext.deleteall('zoo')
  
  -- delete: Delete collection data by id
  -- params: <collection name string>, <id string>
  -- return: None
  appcontext.delete('zoo', 'e898853a-74ee-11e8-941c-9eb6d01c8f95')
  

• message

  -- send: Send message
  -- params: <source string>, <subject string>, <title string>, <msg string>
  -- return: None
  message.send('test_source', 'test_event', 'test_title', 'Test event message.')
  

• json

  -- parse: Parse string to table
  -- params: <json string>
  -- return: <result table>
  local obj = json.parse('{"name":"Tom", "age":12}')
  local arr = json.parse('[{"name":"Tom", "age":12}, {"name":"Jack", "age":10}]')
  
  -- string: json table to string
  -- params: <json table>
  -- return: <result string>
  local str = json.string({name='Tom', age=12})
  

• csv

  -- parse: Parse string to table
  -- params: <csv string>
  -- return: <result table>
  local str = 'Tom,12,BJ'..'\n'..'Jack,13,BJ'
  local arr = csv.parse(str)
  
  -- string: csv table to string (single line)
  -- params: <csv table>
  -- return: <result string>
  local str = csv.string({'Tom', 12, 'BJ'})
  

示例

if ACTION == 'INSERT' then
    odb.mql("insert into /test (id, name) values ('ID1', "..OBJECT.name..")")
    DATACHANGE = true
end