Merge b773a3e into 44f1b13

migrations/0006_make_primary_keys_autoincrement.py

@@ -0,0 +1,79 @@
+"""
+make_pks_autoincrement
+date created: 2019-03-28 21:47:26.858802
+"""
+
+metric_original = """CREATE TABLE `metric` (
+  `metric_id`  INTEGER NOT NULL,
+  `name`  VARCHAR(120) NOT NULL UNIQUE,
+  `units`  VARCHAR(24),
+  `upper_limit`  REAL,
+  `lower_limit`  REAL,
+  PRIMARY KEY(metric_id)
+);"""
+
+metric_new = """CREATE TABLE `metric` (
+  `metric_id`  INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+  `name`  VARCHAR(120) NOT NULL UNIQUE,
+  `units`  VARCHAR(24),
+  `upper_limit`  REAL,
+  `lower_limit`  REAL
+);"""
+
+datapoint_original = """CREATE TABLE `datapoint` (
+  `datapoint_id`  INTEGER NOT NULL,
+  `metric_id`  INTEGER NOT NULL,
+  `value`  REAL NOT NULL,
+  `timestamp`  INTEGER NOT NULL,
+  PRIMARY KEY(datapoint_id),
+  FOREIGN KEY(`metric_id`) REFERENCES "metric" ( "metric_id" ) ON DELETE CASCADE
+);"""
+
+datapoint_new = """CREATE TABLE `datapoint` (
+  `datapoint_id`  INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,
+  `metric_id`  INTEGER NOT NULL,
+  `value`  REAL NOT NULL,
+  `timestamp`  INTEGER NOT NULL,
+  FOREIGN KEY(`metric_id`) REFERENCES "metric" ( "metric_id" ) ON DELETE CASCADE
+);"""
+
+COPY_SQL = """
+/* ===== Begin copy for `{tbl_name}` ===== */
+ALTER TABLE `{tbl_name}` RENAME TO `{tbl_name}_temp`;
+{create_table_sql};
+INSERT INTO `{tbl_name}` SELECT * FROM `{tbl_name}_temp`;
+DROP TABLE `{tbl_name}_temp`;
+"""
+
+def _create_copy_sql(tbl_name, create_table_sql):
+    """
+    Generate the SQL to copy one table to another.
+
+    Parameters
+    ----------
+    tbl_name : string
+        The name of the table to copy. The intermediate table will be have
+        "_temp" appended to it.
+    create_table_sql : string
+        The SQL to generate the new table.
+    """
+    # Apparently migrator.execute_sql can only execute one statment at a
+    # time. So we gotta do it one by one. It's *probably* save enough
+    # to split on the semicolon...
+    sql = COPY_SQL.format(tbl_name=tbl_name,
+                          create_table_sql=create_table_sql)
+    return sql.split(";")
+
+
+def upgrade(migrator):
+    sql = _create_copy_sql("metric", metric_new)
+    sql += _create_copy_sql("datapoint", datapoint_new)
+    for line in sql:
+        migrator.execute_sql(line)
+
+
+def downgrade(migrator):
+    sql = _create_copy_sql("metric", metric_original)
+    sql += _create_copy_sql("datapoint", datapoint_original)
+    for line in sql:
+        migrator.execute_sql(line)

src/trendlines/orm.py

@@ -12,6 +12,7 @@
 from peewee import CharField
 from peewee import OperationalError
 from peewee_moves import DatabaseManager
+from playhouse.sqlite_ext import AutoIncrementField
 
 from trendlines import logger
 from trendlines import utils
@@ -60,7 +61,7 @@ class Metric(InternalModel):
     Table holding all of the Metric information.
     """
 
-    metric_id = IntegerField(primary_key=True)
+    metric_id = AutoIncrementField()
     name = CharField(max_length=120, unique=True)
     units = CharField(max_length=24, null=True)
     upper_limit = FloatField(null=True)
@@ -82,7 +83,7 @@ class DataPoint(DataModel):
     naive :class:`datetime.datetime` objects (no timezone info).
     """
 
-    datapoint_id = IntegerField(primary_key=True)
+    datapoint_id = AutoIncrementField()
     metric = ForeignKeyField(Metric, backref="datapoints",
                              on_delete="CASCADE")
     value = FloatField()