Stabilizing candlestick and adding tests

docs/test_candlestick_agg.md

@@ -0,0 +1,90 @@
+# Candlestick Continuous Aggregation Tests
+
+## Setup table
+```SQL,non-transactional,ignore-output
+SET TIME ZONE 'UTC';
+CREATE TABLE stocks_real_time (
+  time TIMESTAMPTZ NOT NULL,
+  symbol TEXT NOT NULL,
+  price DOUBLE PRECISION NULL,
+  day_volume INT NULL
+);
+SELECT create_hypertable('stocks_real_time','time');
+CREATE INDEX ix_symbol_time ON stocks_real_time (symbol, time DESC);
+
+CREATE TABLE company (
+  symbol TEXT NOT NULL,
+  name TEXT NOT NULL
+);
+```
+
+## Setup Continuous Aggs
+```SQL,non-transactional,ignore-output
+CREATE MATERIALIZED VIEW candlestick
+WITH (timescaledb.continuous) AS
+SELECT time_bucket('1 minute'::interval, "time") AS ts,
+  symbol,
+  candlestick_agg("time", price, day_volume) AS candlestick
+FROM stocks_real_time
+GROUP BY ts, symbol;
+```
+
+## Insert data into table
+```SQL,non-transactional,ignore-output
+INSERT INTO stocks_real_time("time","symbol","price","day_volume")
+VALUES
+('2023-01-11 17:59:57-06','AAPL',133.445,NULL),
+('2023-01-11 17:59:55-06','PFE',47.38,NULL),
+('2023-01-11 17:59:54-06','AMZN',95.225,NULL),
+('2023-01-11 17:59:52-06','AAPL',29.82,NULL);
+```
+
+```SQL,non-transactional,ignore-output
+INSERT INTO company("symbol","name")
+VALUES
+('AAPL','Apple'),
+('PFE','Pfizer'),
+('AMZN','Amazon');
+```
+## Query by-minute continuous aggregate over stock trade data for ohlc prices along with timestamps 
+
+```SQL,non-transactional,ignore-output
+SELECT ts,
+  symbol,
+    open_time(candlestick),
+    open(candlestick),
+    high_time(candlestick),
+    high(candlestick),
+    low_time(candlestick),
+    low(candlestick),
+    close_time(candlestick),
+    close(candlestick)
+FROM candlestick;
+```
+
+```output
+           ts           | symbol |       open_time        |  open  |       high_time        |  high   |        low_time        |  low   |       close_time       |  close
+------------------------+--------+------------------------+--------+------------------------+---------+------------------------+--------+------------------------+---------
+ 2023-01-11 23:59:00+00 | PFE    | 2023-01-11 23:59:55+00 |  47.38 | 2023-01-11 23:59:55+00 |   47.38 | 2023-01-11 23:59:55+00 |  47.38 | 2023-01-11 23:59:55+00 |   47.38
+ 2023-01-11 23:59:00+00 | AAPL   | 2023-01-11 23:59:52+00 |  29.82 | 2023-01-11 23:59:57+00 | 133.445 | 2023-01-11 23:59:52+00 |  29.82 | 2023-01-11 23:59:57+00 | 133.445
+ 2023-01-11 23:59:00+00 | AMZN   | 2023-01-11 23:59:54+00 | 95.225 | 2023-01-11 23:59:54+00 |  95.225 | 2023-01-11 23:59:54+00 | 95.225 | 2023-01-11 23:59:54+00 |  95.225
+```
+
+## Roll up your by minute continuous agg into daily buckets and return the volume weighted average price for AAPL and its high price
+
+```SQL,non-transactional,ignore-output
+SELECT
+    time_bucket('1 day'::interval, ts) AS daily_bucket,
+    symbol,
+    vwap(rollup(candlestick)),
+	high(rollup(candlestick))
+FROM candlestick
+WHERE symbol = 'AAPL'
+GROUP BY daily_bucket,symbol;
+```
+
+```output
+      daily_bucket      | symbol | vwap |  high
+------------------------+--------+------+---------
+ 2023-01-11 00:00:00+00 | AAPL   | NULL | 133.445
+```

extension/src/accessors.rs

@@ -89,7 +89,14 @@ accessor! { first_val() }
 accessor! { last_val() }
 accessor! { first_time() }
 accessor! { last_time() }
-
+accessor! { open()}
+accessor! { close()}
+accessor! { high()}
+accessor! { low()}
+accessor! { open_time()}
+accessor! { high_time()}
+accessor! { low_time()}
+accessor! { close_time()}
 // The rest are more complex, with String or other challenges.  Leaving alone for now.
 
 pg_type! {