Lua driver for Exasol

• Index

Contents

• Local Functions
• Methods

Classes

• luasql.exasol.Connection
• luasql.exasol.ConnectionProperties
• luasql.exasol.Cursor
• luasql.exasol.CursorData
• luasql.exasol.Environment
• luasql.exasol.ExasolWebsocket
• luasql.exasol.Websocket
• luasql.exasol.WebsocketDatahandler

Modules

• luasql.exasol
• luasql.exasol.constants
• luasql.exasol.util

Examples

• examples.lua

Class luasql.exasol.CursorData

This internal class represents the result data of a cursor that allows retreiving rows from a result set.

It handles large result sets by fetching new batches automatically.

Local Functions

luasql.exasol.cursordata.convert_col_value(col_value)

Convert a column value if necessary before returining it.

Methods

luasql.exasol.cursordata:create(connection_properties, websocket, result_set)	Create a new instance of the CursorData class.
luasql.exasol.cursordata:next_row()	Advances the cursor data to the next row.
luasql.exasol.cursordata:get_current_row()	Get the current row number.
luasql.exasol.cursordata:has_more_rows()	Check if there are more rows available in the result set.
luasql.exasol.cursordata:get_column_value(column_index)	Get a column value from the current row.
luasql.exasol.cursordata:_fetch_data()	Fetch the next batch of data if no more rows are available locally.
luasql.exasol.cursordata:_end_of_result_set_reached()	Check if the cursor has reached the last row of the complete result set.
luasql.exasol.cursordata:_more_data_available()	Check if more rows are available in the current batch or if the next batch must be fetched.
luasql.exasol.cursordata:_fetch_next_data_batch()	Fetches the next batch of the result set from the database.

Local Functions

Methods

luasql.exasol.cursordata.convert_col_value(col_value) line 75

Convert a column value if necessary before returining it. We need to replace cjson.null with luasql.exasol.NULL to hide the implementation detail that we are using cjson for JSON parsing.

Parameters:

• col_value

Methods

luasql.exasol.cursordata:create(connection_properties, websocket, result_set) line 31

Create a new instance of the CursorData class.

Parameters:

• connection_properties luasql.exasol.ConnectionProperties the user defined connection settings, containing e.g. fetch size
• websocket luasql.exasol.ExasolWebsocket the websocket connection to the database
• result_set table the result set received when executing a query

Returns:

luasql.exasol.CursorData a new CursorData instance

Raises:

an error in case the result set is invalid

luasql.exasol.cursordata:next_row() line 55

Advances the cursor data to the next row.

luasql.exasol.cursordata:get_current_row() line 62

Get the current row number.

Returns:

number the current row number (starting with 1) of the complete result set

luasql.exasol.cursordata:has_more_rows() line 68

Check if there are more rows available in the result set.

Returns:

boolean true if there are more rows available

luasql.exasol.cursordata:get_column_value(column_index) line 87

Get a column value from the current row. Fetches the next batch in case not enough data is available.

Parameters:

• column_index number the column index starting with 1

Returns:

any the value of the given column

luasql.exasol.cursordata:_fetch_data() line 105

Fetch the next batch of data if no more rows are available locally.

luasql.exasol.cursordata:_end_of_result_set_reached() line 123

Check if the cursor has reached the last row of the complete result set.

luasql.exasol.cursordata:_more_data_available() line 128

Check if more rows are available in the current batch or if the next batch must be fetched.

luasql.exasol.cursordata:_fetch_next_data_batch() line 133

Fetches the next batch of the result set from the database.