TimescaleDB Helpers

Connection

Function	Parameters	Returns
`timescaledb_connect(connstr, pool_size)`	`connstr`: PostgreSQL connection string (e.g. `"host=localhost port=5432 dbname=iotsensors user=postgres password=secret sslmode=disable"`), `pool_size` (optional): max connections (default 5, min 1)	`(success, error_msg)` — boolean + string\|nil
`timescaledb_disconnect()`	none	`(success, error_msg)` — boolean + string\|nil

TLS not supported; use sslmode=disable. Connection persists across all hooks.

Block until confirmed. Raise Lua errors on failure — wrap in pcall() for error handling.

Function	Parameters	Returns
`timescaledb_execute(sql, params)`	`sql`: SQL with `$1`, `$2` placeholders, `params` (optional): array of values (string/number/boolean/nil)	`rows_affected` (number)
`timescaledb_insert(table_name, columns, values)`	`table_name`: string, `columns`: array of column names, `values`: array of values matching columns	`rows_affected` (number)
`timescaledb_insert_batch(table_name, columns, rows)`	`table_name`: string, `columns`: array of column names, `rows`: array of row arrays	`rows_affected` (number)

Parameter limit: max 65,535 bind parameters. For batch: columns × rows must not exceed 65,535.

Fire-and-forget. Errors logged internally, never raise Lua errors.

Function	Parameters	Returns
`timescaledb_execute_async(sql, params)`	Same as `timescaledb_execute`	`true` if queued, `false` if validation failed
`timescaledb_insert_async(table_name, columns, values)`	Same as `timescaledb_insert`	`true` if queued, `false` if validation failed
`timescaledb_insert_batch_async(table_name, columns, rows)`	Same as `timescaledb_insert_batch`	`true` if queued, `false` if validation failed

Lua Type	PostgreSQL Types
`nil`	Any (as NULL)
`string`	TEXT, VARCHAR, CHAR, BPCHAR, NAME
`number` (int)	INT2, INT4, INT8, NUMERIC (range-checked)
`number` (float)	FLOAT4, FLOAT8, NUMERIC (range-checked for FLOAT4)
`boolean`	BOOL