Embedded Systems LM5p-GSM, Руководство по эксплуатации продукта

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address = grp.create({
datatype = dt.bool,
name = 'My second object',
})
Database functions
SQLite v3 is used as the database engine.
Note: Database tables must be prefixed with unique application name to minimize collisions
between different applications.
Core functions
•
db:execute(query) – executes given query, return value can be either a database cursor
or query result
•
db:escape(value) – escapes given string value so it can be safely used in a query
•
db:query(query, …) – executes given query, question marks in the query are replaced by
additional parameters (see examples below)
INSERT/UPDATE/DELETE helpers
Note: Lua tables passed as values and where parameters must not have fields that are not
present in given database table. Otherwise query will fail
•
db:insert(tablename, values) – performs INSERT query based on given values
•
db:update(tablename, values, where) – performs UPDATE query based on given values
and where parameters
•
db:delete(tablename, where) – performs DELETE query based on where parameter
SELECT helpers
Note: parameters must be passed in the same way as for db:query() function
•
db:getone(query, …) – returns first field value from the first matching row from given
query
• db:getrow(query, …) – returns first matching row from given query
•
db:getlist(query, …) – returns complete query result as Lua table , where each table item
is first field from each row
•
db:getall(query, …) – returns complete query result as Lua table , where each table item
is Lua table with field→value mapping