Restructuring Database.Connection to allow for database specific ty…

…pes. (#3632)

- Added `databases`, `database`, `set_database`.
- Added `schemas`, `schema`, `set_schema`.
- Added `table_types`,
- Added `tables`.
- Moved the vast majority of the connection work into a lower level `JDBC_Connection` object.
- `Connection` represents the standard API for database connections and provides a base JDBC implementation.
- `SQLite_Connection` has the `Connection` API but with custom `databases` and `schemas` methods for SQLite.
- `Postgres_Connection` has the `Connection` API but with custom `set_database`, `databases`, `set_schema` and `schemas` methods for Postgres.
- Updated `Redshift` - no public API change.

CHANGELOG.md

@@ -191,6 +191,7 @@
 - [Implemented `Table.take` and `Table.drop` for the in-memory backend.][3647]
 - [Implemented specialized storage for the in-memory Table.][3673]
 - [Implemented `Table.distinct` for the in-memory backend.][3684]
+- [Added `databases`, `schemas`, `tables` support to database Connection.][3632]
 
 [debug-shortcuts]:
   https://github.com/enso-org/enso/blob/develop/app/gui/docs/product/shortcuts.md#debug
@@ -293,6 +294,7 @@
 [3617]: https://github.com/enso-org/enso/pull/3617
 [3628]: https://github.com/enso-org/enso/pull/3628
 [3629]: https://github.com/enso-org/enso/pull/3629
+[3632]: https://github.com/enso-org/enso/pull/3632
 [3641]: https://github.com/enso-org/enso/pull/3641
 [3643]: https://github.com/enso-org/enso/pull/3643
 [3644]: https://github.com/enso-org/enso/pull/3644

distribution/lib/Standard/Database/0.0.0-dev/src/Connection/Postgres.enso

@@ -2,13 +2,16 @@ from Standard.Base import all
 
 from Standard.Base.Data.Numbers import Parse_Error_Data
 
-import Standard.Database.Data.Dialect
-import Standard.Database.Connection.Connection
-from Standard.Database.Connection.Credentials import Credentials_Data, Credentials
+import Standard.Database.Internal.Postgres.Postgres_Connection
 import Standard.Database.Connection.Connection_Options
+
+from Standard.Database.Connection.Credentials import Credentials, Credentials_Data
+
 import Standard.Database.Connection.SSL_Mode
 from Standard.Database.Connection.SSL_Mode import all
+
 import Standard.Database.Connection.Client_Certificate
+
 import Standard.Database.Internal.Postgres.Pgpass
 
 polyglot java import org.postgresql.Driver
@@ -20,10 +23,11 @@ type Postgres
        - host: The hostname of the database server (defaults to localhost).
        - port: The port of the database server (defaults to 5432).
        - database: The database to connect to. If empty, the default database will be used.
+       - schema: The schema to connect to. If empty, the default schema will be used.
        - credentials: The credentials to use for the connection (defaults to PGPass or No Authentication).
        - use_ssl: Whether to use SSL (defaults to `Prefer`).
        - client_cert: The client certificate to use or `Nothing` if not needed.
-    Postgres_Data (host:Text=default_postgres_host) (port:Integer=default_postgres_port) (database:Text=default_postgres_database) (credentials:(Credentials|Nothing)=Nothing) (use_ssl:SSL_Mode=Prefer) (client_cert:(Client_Certificate|Nothing)=Nothing)
+    Postgres_Data (host:Text=default_postgres_host) (port:Integer=default_postgres_port) (database:Text=default_postgres_database) (schema:Text="") (credentials:(Credentials|Nothing)=Nothing) (use_ssl:SSL_Mode=Prefer) (client_cert:(Client_Certificate|Nothing)=Nothing)
 
     ## Build the Connection resource.
 
@@ -34,7 +38,12 @@ type Postgres
         if Driver.isRegistered.not then Driver.register
 
         properties = options.merge self.jdbc_properties
-        Connection.create_jdbc_connection self.jdbc_url properties self.dialect
+
+        ## Cannot use default argument values as gets in an infinite loop if you do.
+        make_new database schema =
+            Postgres_Data self.host self.port (database.if_nothing self.database) (schema.if_nothing self.schema) self.credentials self.use_ssl self.client_cert . connect options
+
+        Postgres_Connection.create self.jdbc_url properties make_new
 
     ## Provides the jdbc url for the connection.
     jdbc_url : Text
@@ -65,11 +74,7 @@ type Postgres
         cert_properties = if self.client_cert.is_nothing then [] else
             self.client_cert.properties
 
-        credentials + ssl_properties + cert_properties
-
-    ## Provides the dialect needed for creating SQL statements.
-    dialect : Dialect
-    dialect self = Dialect.postgres
+        (if self.schema == '' then [] else [Pair_Data 'currentSchema' self.schema]) + credentials + ssl_properties + cert_properties
 
 ## PRIVATE
    Given an `SSL_Mode`, create the JDBC properties to secure a Postgres-based

distribution/lib/Standard/Database/0.0.0-dev/src/Connection/Redshift.enso

@@ -1,6 +1,7 @@
 from Standard.Base import all
 
 import Standard.Database.Data.Dialect
+import Standard.Database.Internal.JDBC_Connection
 import Standard.Database.Connection.Connection
 from Standard.Database.Connection.Credentials import Credentials, Credentials_Data
 import Standard.Database.Connection.Connection_Options
@@ -37,7 +38,9 @@ type Redshift
         java_props = Properties.new
         properties.each pair->
             java_props.setProperty pair.first pair.second
-        Connection.create_jdbc_connection self.jdbc_url properties self.dialect
+
+        jdbc_connection = JDBC_Connection.create self.jdbc_url properties
+        Connection.Connection_Data jdbc_connection Dialect.redshift
 
     ## Provides the jdbc url for the connection.
     jdbc_url : Text
@@ -54,11 +57,11 @@ type Redshift
         credentials = case self.credentials of
             Nothing -> Pgpass.read self.host self.port self.schema
             AWS_Profile db_user profile ->
-                [Pair 'user' db_user] + (if profile == '' then [] else [Pair 'profile' profile])
+                [Pair_Data 'user' db_user] + (if profile == '' then [] else [Pair_Data 'profile' profile])
             AWS_Key db_user access_key secret_access_key ->
-                [Pair 'user' db_user, Pair 'AccessKeyID' access_key, Pair 'SecretAccessKey' secret_access_key]
+                [Pair_Data 'user' db_user, Pair_Data 'AccessKeyID' access_key, Pair_Data 'SecretAccessKey' secret_access_key]
             Credentials_Data username password ->
-                [Pair 'user' username, Pair 'password' password]
+                [Pair_Data 'user' username, Pair_Data 'password' password]
 
         ## Disabled as Redshift SSL settings are different to PostgreSQL.
         ssl_properties = []
@@ -68,10 +71,6 @@ type Redshift
 
         credentials + ssl_properties + cert_properties
 
-    ## Provides the dialect needed for creating SQL statements.
-    dialect : Dialect
-    dialect self = Dialect.redshift
-
 type AWS_Credential
     ## Access Redshift using IAM via an AWS profile.
 
@@ -80,7 +79,6 @@ type AWS_Credential
        - profile: AWS profile name (if empty uses default).
     AWS_Profile db_user:Text profile:Text=''
 
-
     ## Access Redshift using IAM via an AWS access key ID and secret access key.
 
        Arguments:

distribution/lib/Standard/Database/0.0.0-dev/src/Connection/SQLite.enso

@@ -1,18 +1,23 @@
 from Standard.Base import all
 
-import Standard.Database.Data.Dialect
-import Standard.Database.Connection.Connection
+import Standard.Database.Internal.SQLite.SQLite_Connection
 import Standard.Database.Connection.Connection_Options
 
-## Connect to a SQLite DB File or InMemory DB.
 type SQLite
+    ## Connect to a SQLite DB File or InMemory DB.
+
+       Arguments:
+       - location: Location of the SQLite database to connect to.
     SQLite_Data (location:(In_Memory|File|Text))
 
     ## Build the Connection resource.
+
+       Arguments:
+       - options: Overrides for the connection properties.
     connect : Connection_Options
     connect self options =
         properties = options.merge self.jdbc_properties
-        Connection.create_jdbc_connection self.jdbc_url properties self.dialect
+        SQLite_Connection.create self.jdbc_url properties
 
     ## Provides the jdbc url for the connection.
     jdbc_url : Text
@@ -24,9 +29,5 @@ type SQLite
     jdbc_properties : Vector
     jdbc_properties self = []
 
-    ## Provides the dialect needed for creating SQL statements.
-    dialect : Dialect
-    dialect self = Dialect.sqlite
-
 ## Connect to an in-memory SQLite database.
 type In_Memory

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Column.enso

@@ -9,7 +9,7 @@ import Standard.Table.Data.Sort_Column
 
 from Standard.Database.Data.Sql import Sql_Type
 from Standard.Database.Data.Table import Integrity_Error
-from Standard.Database.Error import Unsupported_Database_Operation_Error
+from Standard.Database.Errors import Unsupported_Database_Operation_Error
 
 type Column
 

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Dialect/Postgres.enso

@@ -8,7 +8,7 @@ import Standard.Database.Data.Dialect
 import Standard.Database.Data.Dialect.Helpers
 import Standard.Database.Data.Internal.Base_Generator
 import Standard.Database.Data.Internal.IR
-from Standard.Database.Error import Unsupported_Database_Operation_Error
+from Standard.Database.Errors import Unsupported_Database_Operation_Error
 
 ## PRIVATE
 

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Dialect/SQLite.enso

@@ -7,7 +7,7 @@ import Standard.Database.Data.Dialect
 import Standard.Database.Data.Dialect.Helpers
 import Standard.Database.Data.Internal.Base_Generator
 import Standard.Database.Data.Internal.IR
-from Standard.Database.Error import Unsupported_Database_Operation_Error_Data
+from Standard.Database.Errors import Unsupported_Database_Operation_Error_Data
 
 ## PRIVATE
 

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Internal/Aggregate_Helper.enso

@@ -4,7 +4,7 @@ from Standard.Base.Data.Text.Text_Ordering import Text_Ordering_Data
 from Standard.Table.Data.Aggregate_Column import all
 import Standard.Database.Data.Internal.IR
 from Standard.Database.Data.Sql import Sql_Type
-from Standard.Database.Error import Unsupported_Database_Operation_Error_Data
+from Standard.Database.Errors import Unsupported_Database_Operation_Error_Data
 
 ## PRIVATE
    Creates an `Internal_Column` that computes the specified statistic.

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Internal/Base_Generator.enso

@@ -4,7 +4,7 @@ import Standard.Database.Data.Sql
 import Standard.Database.Data.Internal.IR
 
 from Standard.Database.Data.Sql import Sql_Type
-from Standard.Database.Error import Unsupported_Database_Operation_Error
+from Standard.Database.Errors import Unsupported_Database_Operation_Error
 
 type Internal_Dialect
 

distribution/lib/Standard/Database/0.0.0-dev/src/Data/Table.enso

@@ -21,7 +21,7 @@ from Standard.Database.Data.Internal.IR import Internal_Column, Internal_Column_
 from Standard.Table.Errors import No_Such_Column_Error, No_Such_Column_Error_Data
 from Standard.Table.Data.Column_Selector import Column_Selector, By_Index, By_Name
 from Standard.Table.Data.Data_Formatter import Data_Formatter
-from Standard.Database.Error import Unsupported_Database_Operation_Error_Data
+from Standard.Database.Errors import Unsupported_Database_Operation_Error_Data
 import Standard.Table.Data.Column_Name_Mapping
 import Standard.Table.Data.Position
 import Standard.Table.Data.Sort_Column_Selector

distribution/lib/Standard/Database/0.0.0-dev/src/Errors.enso

@@ -0,0 +1,80 @@
+from Standard.Base import all
+
+polyglot java import java.sql.SQLException
+
+## Indicates that a requested operation is not supported, for example because a
+   particular database backend does not support it.
+type Unsupported_Database_Operation_Error
+    Unsupported_Database_Operation_Error_Data message
+
+    ## UNSTABLE
+
+       Convert the SQL error to a textual representation.
+    to_text : Text
+    to_text self =
+        "Unsupported database operation: " + self.message
+
+    ## UNSTABLE
+
+       Pretty print the error.
+    to_display_text : Text
+    to_display_text self =
+        "Unsupported database operation: " + self.message
+
+type Sql_Error
+    ## UNSTABLE
+
+       Indicates an error with executing a query, update or connecting to the
+       database.
+
+       Arguments:
+       - java_exception: The underlying exception.
+       - related_query (optional): A string representation of a query that this
+         error is related to.
+    Sql_Error_Data java_exception related_query=Nothing
+
+    ## UNSTABLE
+
+       Convert the SQL error to a textual representation.
+    to_text : Text
+    to_text self =
+        query = if self.related_query.is_nothing.not then " [Query was: " + self.related_query + "]" else ""
+        "There was an SQL error: " + self.java_exception.getMessage.to_text + "." + query
+
+    ## UNSTABLE
+
+       Pretty print the SQL error.
+    to_display_text : Text
+    to_display_text self = self.to_text
+
+    ## PRIVATE
+
+       Throws an error as if a SQL Exception was thrown.
+    throw_sql_error : Text -> Sql_Error
+    throw_sql_error message =
+        Error.throw (Sql_Error_Data (SQLException.new message))
+
+type Sql_Timeout_Error
+    ## UNSTABLE
+
+       Indicates that an operation has timed out.
+
+       Arguments:
+       - java_exception: The underlying exception.
+       - related_query (optional): A string representation of a query that this
+         error is related to.
+    Sql_Timeout_Error_Data java_exception related_query=Nothing
+
+    ## UNSTABLE
+
+       Convert the timeout error to a textual representation.
+    to_text : Text
+    to_text self =
+        query = if self.related_query.is_nothing.not then " [Query was: " + query + "]" else ""
+        "The SQL connection timed out: " + self.java_exception.getMessage + "." + query
+
+    ## UNSTABLE
+
+       Pretty print the timeout error.
+    to_display_text : Text
+    to_display_text self = self.to_text