Update rename_columns to new API design, add first_row, `second_r…

…ow` and `last_row` functions to the table. (#5719)

- Updates the `rename_columns` API.
- Add `first_row`, `second_row` and `last_row` to the Table types.
- New option for reading only last row of ResultSet.

CHANGELOG.md

@@ -323,6 +323,8 @@
 - [`File.parent` may return `Nothing`.][5699]
 - [Removed non-regex functionality from `is_match`, `match`, and `match_all`,
   and renamed them to `match`, `find`, `find_all` (respectively).][5721]
+- [Updated `rename_columns` to new API. Added `first_row`, `second_row` and
+  `last_row` to Table types][5719]
 
 [debug-shortcuts]:
   https://github.com/enso-org/enso/blob/develop/app/gui/docs/product/shortcuts.md#debug
@@ -493,9 +495,10 @@
 [5645]: https://github.com/enso-org/enso/pull/5645
 [5646]: https://github.com/enso-org/enso/pull/5646
 [5656]: https://github.com/enso-org/enso/pull/5656
+[5678]: https://github.com/enso-org/enso/pull/5678
 [5679]: https://github.com/enso-org/enso/pull/5679
 [5699]: https://github.com/enso-org/enso/pull/5699
-[5678]: https://github.com/enso-org/enso/pull/5678
+[5719]: https://github.com/enso-org/enso/pull/5719
 [5721]: https://github.com/enso-org/enso/pull/5721
 
 #### Enso Compiler

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Text/Case_Sensitivity.enso

@@ -1,4 +1,6 @@
 import project.Data.Locale.Locale
+import project.Data.Text.Regex
+import project.Data.Text.Text
 
 from project.Data.Boolean import Boolean, True, False
 
@@ -29,9 +31,19 @@ type Case_Sensitivity
             TextFoldingStrategy.caseInsensitiveFold locale.java_locale
 
     ## PRIVATE
-       Is case insensitive.
-    is_case_insensitive : Boolean
-    is_case_insensitive self = case self of
+       Is case insensitive when in memory.
+    is_case_insensitive_in_memory : Boolean
+    is_case_insensitive_in_memory self = case self of
         Case_Sensitivity.Default -> False
         Case_Sensitivity.Sensitive -> False
         Case_Sensitivity.Insensitive _ -> True
+
+    ## PRIVATE
+       Create matcher function
+    create_match_function : Boolean -> (Text -> Text -> Boolean)
+    create_match_function self use_regex=False = case use_regex of
+        True -> (name-> pattern-> Regex.compile pattern case_insensitive=self.is_case_insensitive_in_memory . matches name)
+        False -> case self of
+            Case_Sensitivity.Default -> (==)
+            Case_Sensitivity.Sensitive -> (==)
+            Case_Sensitivity.Insensitive locale -> (name-> criterion-> name.equals_ignore_case criterion locale)

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Text/Extensions.enso

@@ -229,7 +229,7 @@ Text.characters self =
              "aabbbbccccaaBcaaaa".find "a[ab]c" Case_Sensitivity.Insensitive
 Text.find : Text -> Case_Sensitivity -> Match | Nothing ! Compile_Error
 Text.find self pattern=".*" case_sensitivity=Case_Sensitivity.Sensitive =
-    case_insensitive = case_sensitivity.is_case_insensitive
+    case_insensitive = case_sensitivity.is_case_insensitive_in_memory
     Regex.compile pattern case_insensitive=case_insensitive . match self Matching_Mode.First
 
 ## Finds all the matches of the regular expression `pattern` in `self`,
@@ -251,7 +251,7 @@ Text.find self pattern=".*" case_sensitivity=Case_Sensitivity.Sensitive =
              "aABbbbccccaaBCaaaa".find_all "a[ab]+c" Case_Sensitivity.Insensitive
 Text.find_all : Text -> Case_Sensitivity -> Vector Match ! Compile_Error
 Text.find_all self pattern=".*" case_sensitivity=Case_Sensitivity.Sensitive =
-    case_insensitive = case_sensitivity.is_case_insensitive
+    case_insensitive = case_sensitivity.is_case_insensitive_in_memory
     case Regex.compile pattern case_insensitive=case_insensitive . match self Regex_Mode.All of
         Nothing -> []
         matches -> matches
@@ -278,7 +278,7 @@ Text.find_all self pattern=".*" case_sensitivity=Case_Sensitivity.Sensitive =
              "[email protected]".match regex Case_Sensitivity.Insensitive
 Text.match : Text -> Case_Sensitivity -> Boolean ! Compile_Error
 Text.match self pattern=".*" case_sensitivity=Case_Sensitivity.Sensitive =
-    case_insensitive = case_sensitivity.is_case_insensitive
+    case_insensitive = case_sensitivity.is_case_insensitive_in_memory
     compiled_pattern = Regex.compile pattern case_insensitive=case_insensitive
     compiled_pattern.matches self
 

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Text/Regex/Pattern.enso

@@ -64,7 +64,7 @@ type Pattern
        Splits the `input` text based on the pattern described by `self`.
 
        Arguments:
-       - input: The text to splut based on the pattern described by `self`.
+       - input: The text to split based on the pattern described by `self`.
        - mode: The splitting mode to use. This must default to `Regex_Mode.All`.
 
        This method will _always_ return a vector. If no splits take place, the

distribution/lib/Standard/Base/0.0.0-dev/src/Data/Vector.enso

@@ -1034,12 +1034,13 @@ type Builder
              builder = Vector.new_builder
              builder . append_vector_range [20, 30, 40, 50] 1 3 . to_vector == [30, 40]
     append_vector_range : Vector Any ! Error -> Integer -> Integer -> Builder ! Error
-    append_vector_range self vector start end =
+    append_vector_range self vector start=0 end=vector.length =
         subrange = vector.slice start end
         ## This workaround is needed because
            `self.java_builder.addAll subrange.to_array` fails with
            `Unsupported argument types: [Array]`.
-        self.java_builder.appendTo subrange.to_array
+        append_result = self.java_builder.appendTo subrange.to_array
+        append_result.if_not_error self
 
     ## PRIVATE
        Appends a new element into this builder.

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

@@ -1,7 +1,6 @@
 from Standard.Base import all
 import Standard.Base.Error.Illegal_State.Illegal_State
 
-from Standard.Table import Column_Name_Mapping
 import Standard.Table.Data.Table.Table as Materialized_Table
 
 import project.Data.SQL_Query.SQL_Query
@@ -103,7 +102,7 @@ type Connection
             table = result_set_to_table <|
                 metadata.getTables database schema name_like types_array
 
-            renamed = table.rename_columns (Column_Name_Mapping.By_Name name_map)
+            renamed = table.rename_columns name_map
             if all_fields then renamed else
                 renamed.select_columns ["Database", "Schema", "Name", "Type", "Description"]
 
@@ -141,11 +140,26 @@ type Connection
 
     ## PRIVATE
        Internal read function for a statement with optional types.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
     read_statement : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
     read_statement self statement expected_types=Nothing =
         self.jdbc_connection.with_prepared_statement statement stmt->
             result_set_to_table stmt.executeQuery expected_types
 
+    ## PRIVATE
+       Internal read function for a statement with optional types returning just last row.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
+    read_last_row : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
+    read_last_row self statement expected_types=Nothing =
+        self.jdbc_connection.with_prepared_statement statement stmt->
+            result_set_to_table stmt.executeQuery expected_types True
+
     ## ADVANCED
 
        Executes a raw update query. If the query was inserting, updating or

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

@@ -8,7 +8,7 @@ import Standard.Base.Error.Illegal_State.Illegal_State
 import Standard.Base.Error.Incomparable_Values.Incomparable_Values
 import Standard.Base.Error.Unimplemented.Unimplemented
 
-from Standard.Table import Auto_Detect, Aggregate_Column, Data_Formatter, Column_Name_Mapping, Column_Selector, Sort_Column, Match_Columns, Position, Set_Mode
+from Standard.Table import Auto_Detect, Aggregate_Column, Data_Formatter, Column_Selector, Sort_Column, Match_Columns, Position, Set_Mode
 import Standard.Table.Data.Column_Type_Selection.Column_Type_Selection
 import Standard.Table.Data.Expression.Expression
 import Standard.Table.Data.Expression.Expression_Error
@@ -359,12 +359,22 @@ type Table
                other, a `Duplicate_Output_Column_Names`.
 
        > Example
-         Rename the first column to "FirstColumn"
+         Rename the "Alpha" column to "Beta"
 
-              table.rename_columns (Column_Name_Mapping.By_Position ["FirstColumn"])
+              table.rename_columns (Map.from_vector [["Alpha", "Beta"]])
 
        > Example
-         Rename the first column to "FirstColumn" passed as a Vector
+         Rename the last column to "LastColumn"
+
+              table.rename_columns (Map.from_vector [[-1, "LastColumn"]])
+
+       > Example
+         Rename the "Alpha" column to "Beta" and last column to "LastColumn"
+
+              table.rename_columns (Map.from_vector [["Alpha", "Beta"], [-1, "LastColumn"]])
+
+       > Example
+         Rename the first column to "FirstColumn"
 
               table.rename_columns ["FirstColumn"]
 
@@ -376,18 +386,12 @@ type Table
        > Example
          For all columns starting with the prefix `name=`, replace it with `key:`.
 
-              table.rename_columns (Column_Name_Mapping.By_Name (Map.from_vector [["name=(.*)", "key:$1"]]) Regex_Matcher.Value)
-    rename_columns : Map | Vector Text | Column_Name_Mapping -> Boolean -> Problem_Behavior -> Table ! Missing_Input_Columns | Column_Indexes_Out_Of_Range | Ambiguous_Column_Rename | Too_Many_Column_Names_Provided | Invalid_Output_Column_Names | Duplicate_Output_Column_Names
-    rename_columns self (column_map=(Column_Name_Mapping.By_Position ["Column"])) (error_on_missing_columns=True) (on_problems=Report_Warning) = case column_map of
-        _ : Vector ->
-            self.rename_columns (Column_Name_Mapping.By_Position column_map) error_on_missing_columns on_problems
-        _ : Map ->
-            self.rename_columns (Column_Name_Mapping.By_Name column_map) error_on_missing_columns on_problems
-        _ ->
-            case Table_Helpers.rename_columns internal_columns=self.internal_columns mapping=column_map error_on_missing_columns=error_on_missing_columns on_problems=on_problems of
-                new_names ->
-                    new_columns = self.internal_columns.map_with_index i->c->(c.rename (new_names.at i))
-                    self.updated_columns new_columns
+              by_name = Column_Selector.By_Name "name=(.*)" Case_Sensitivity.Sensitive use_regex=True
+              table.rename_columns (Map.from_vector [[by_name, "key:$1"]])
+    rename_columns : Map (Text | Integer | Column_Selector) Text | Vector Text -> Boolean -> Problem_Behavior -> Table ! Missing_Input_Columns | Column_Indexes_Out_Of_Range | Ambiguous_Column_Rename | Too_Many_Column_Names_Provided | Invalid_Output_Column_Names | Duplicate_Output_Column_Names
+    rename_columns self column_map=["Column"] (error_on_missing_columns=True) (on_problems=Report_Warning) =
+        new_names = Table_Helpers.rename_columns internal_columns=self.internal_columns mapping=column_map error_on_missing_columns=error_on_missing_columns on_problems=on_problems
+        new_names.if_not_error (self.updated_columns (self.internal_columns.map c-> c.rename (new_names.at c.name)))
 
     ## PRIVATE
 
@@ -702,6 +706,30 @@ type Table
     rows self max_rows=1000 =
         self.read max_rows=max_rows . rows
 
+    ## Returns the first row of the table.
+
+       In the database backend, it first materializes the table to in-memory.
+    first_row : Row ! Index_Out_Of_Bounds
+    first_row self =
+        self.read max_rows=1 . rows . first
+
+    ## Returns the second row of the table.
+
+       In the database backend, it first materializes the table to in-memory.
+    second_row : Row ! Index_Out_Of_Bounds
+    second_row self =
+        self.read max_rows=2 . rows . second
+
+    ## Returns the last row of the table.
+
+       In the database backend, it first materializes the table to in-memory.
+    last_row : Row ! Index_Out_Of_Bounds
+    last_row self =
+        if self.internal_columns.is_empty then Error.throw (Illegal_Argument.Error "Cannot create a table with no columns.") else
+            sql = self.to_sql
+            expected_types = self.internal_columns.map .sql_type
+            self.connection.read_last_row sql expected_types . rows . first
+
     ## ALIAS sort
        Sorts the rows of the table according to the specified columns and order.
 

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

@@ -19,6 +19,7 @@ polyglot java import java.util.Properties
 polyglot java import java.sql.Connection
 polyglot java import java.sql.DatabaseMetaData
 polyglot java import java.sql.PreparedStatement
+polyglot java import java.sql.ResultSet
 polyglot java import java.sql.SQLException
 polyglot java import java.sql.SQLTimeoutException
 

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

@@ -115,10 +115,24 @@ type Postgres_Connection
 
     ## PRIVATE
        Internal read function for a statement with optional types.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
     read_statement : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
     read_statement self statement expected_types=Nothing =
         self.connection.read_statement statement expected_types
 
+    ## PRIVATE
+       Internal read function for a statement with optional types returning just last row.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
+    read_last_row : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
+    read_last_row self statement expected_types=Nothing =
+        self.connection.read_last_row statement expected_types
+
     ## ADVANCED
 
        Executes a raw update query. If the query was inserting, updating or

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

@@ -25,8 +25,8 @@ read_column result_set column_name =
 
 ## PRIVATE
    Converts a ResultSet into a Materialized_Table.
-result_set_to_table : ResultSet -> (Vector | Nothing) -> Materialized_Table
-result_set_to_table result_set expected_types=Nothing =
+result_set_to_table : ResultSet -> (Vector | Nothing) -> Boolean -> Materialized_Table
+result_set_to_table result_set expected_types=Nothing last_row_only=False =
     metadata = result_set.getMetaData
     ncols = metadata.getColumnCount
     column_names = Vector.new ncols ix-> metadata.getColumnName ix+1
@@ -35,13 +35,25 @@ result_set_to_table result_set expected_types=Nothing =
             typeid = metadata.getColumnType ix+1
             name = metadata.getColumnTypeName ix+1
             SQL_Type.Value typeid name
-    column_builders = column_types.map typ->
-        create_builder typ
-    go has_next = if has_next.not then Nothing else
-        column_builders.map_with_index ix-> builder->
-            builder.fetch_and_append result_set ix+1
-        @Tail_Call go result_set.next
-    go result_set.next
+    column_builders = column_types.map create_builder
+    case last_row_only of
+        True ->
+            ## Not using the `ResultSet.last` as not supported by all connection types.
+            go has_next current = case has_next.not of
+                True ->
+                    if current.is_nothing then Nothing else
+                        column_builders.each_with_index ix-> builder-> builder.append (current.at ix)
+                        Nothing
+                False ->
+                    values = column_builders.map_with_index ix-> builder-> builder.fetch_value result_set ix+1
+                    @Tail_Call go result_set.next values
+            go result_set.next Nothing
+        False ->
+            go has_next = if has_next.not then Nothing else
+                column_builders.map_with_index ix-> builder->
+                    builder.fetch_and_append result_set ix+1
+                @Tail_Call go result_set.next
+            go result_set.next
     columns = column_builders.zip column_names builder-> name->
         builder.make_column name
     Materialized_Table.new columns
@@ -105,25 +117,29 @@ type Builder
        - i: the index of the column to fetch from (starting from 1 as is the
          ResultSet convention).
     fetch_and_append : ResultSet -> Integer -> Nothing
-    fetch_and_append self rs i = case self of
-        Builder.Builder_Inferred _ ->
-            obj = rs.getObject i
-            self.java_builder.append obj
-        Builder.Builder_Boolean _ ->
-            bool = rs.getBoolean i
-            case rs.wasNull of
-                True -> self.java_builder.appendNulls 1
-                False -> self.java_builder.appendBoolean bool
-        Builder.Builder_Long _ ->
-            long = rs.getLong i
-            case rs.wasNull of
-                True -> self.java_builder.appendNulls 1
-                False -> self.java_builder.appendLong long
-        Builder.Builder_Double _ ->
-            double = rs.getDouble i
-            case rs.wasNull of
-                True -> self.java_builder.appendNulls 1
-                False -> self.java_builder.appendDouble double
+    fetch_and_append self rs i =
+        value = self.fetch_value rs i
+        self.append value
+
+    ## PRIVATE
+       Fetches the value of ith column from the current row of the result set
+    fetch_value : ResultSet -> Integer -> Any
+    fetch_value self rs i =
+        value = case self of
+            Builder.Builder_Inferred _ -> rs.getObject i
+            Builder.Builder_Boolean _ -> rs.getBoolean i
+            Builder.Builder_Long _ -> rs.getLong i
+            Builder.Builder_Double _ -> rs.getDouble i
+        if rs.wasNull then Nothing else value
+
+    ## PRIVATE
+    append : Any -> Nothing
+    append self value = if value.is_nothing then self.java_builder.appendNulls 1 else
+        case self of
+            Builder.Builder_Inferred _ -> self.java_builder.append value
+            Builder.Builder_Boolean _ -> self.java_builder.appendBoolean value
+            Builder.Builder_Long _ -> self.java_builder.appendLong value
+            Builder.Builder_Double _ -> self.java_builder.appendDouble value
 
     ## PRIVATE
 

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

@@ -108,10 +108,24 @@ type SQLite_Connection
 
     ## PRIVATE
        Internal read function for a statement with optional types.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
     read_statement : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
     read_statement self statement expected_types=Nothing =
         self.connection.read_statement statement expected_types
 
+    ## PRIVATE
+       Internal read function for a statement with optional types returning just last row.
+
+       Arguments:
+       - statement: SQL_Statement to execute.
+       - expected_types: Optional vector of expected types for each column.
+    read_last_row : SQL_Statement -> (Nothing | Vector SQL_Type) -> Materialized_Table
+    read_last_row self statement expected_types=Nothing =
+        self.connection.read_last_row statement expected_types
+
     ## ADVANCED
 
        Executes a raw update query. If the query was inserting, updating or