Support for selecting / renaming columns when writing to SQLite

Author: King-Ozymandias

src/DataFrame-IO-Sqlite/DataFrame.extension.st

@@ -14,6 +14,16 @@ DataFrame >> writeToSqlite: aSqlite3Connection tableName: aString [
 	self writeTo: aSqlite3Connection using: writer
 ]
 
+{ #category : '*DataFrame-IO-Sqlite' }
+DataFrame >> writeToSqlite: aSqlite3Connection tableName: aString columnMappings: aCollection [
+
+	| writer |
+	writer := DataFrameSqliteColumnMappingWriter 
+		          writeToTable: aString
+		          columnMappings: aCollection.
+	self writeTo: aSqlite3Connection using: writer
+]
+
 { #category : '*DataFrame-IO-Sqlite' }
 DataFrame >> writeToSqlite: aSqlite3Connection tableName: aString columnNames: aCollection [
 

src/DataFrame-IO-Sqlite/DataFrameAbstractSqliteWriter.class.st

@@ -0,0 +1,35 @@
+Class {
+	#name : 'DataFrameAbstractSqliteWriter',
+	#superclass : 'DataFrameWriter',
+	#instVars : [
+		'tableName'
+	],
+	#category : 'DataFrame-IO-Sqlite',
+	#package : 'DataFrame-IO-Sqlite'
+}
+
+{ #category : 'helpers' }
+DataFrameAbstractSqliteWriter >> insertQueryForColumns: aSequence [
+	""
+	^ String streamContents: [ :strm |
+		strm
+			nextPutAll: 'INSERT INTO ';
+			nextPutAll: tableName;
+			nextPut: $(;
+			nextPutAll: (',' join: aSequence);
+			nextPutAll: ')VALUES('.
+		aSequence do: [ :ignore | strm nextPut: $? ] separatedBy: [ strm nextPut: $, ].
+		strm nextPut: $) ]
+]
+
+{ #category : 'accessing' }
+DataFrameAbstractSqliteWriter >> tableName [
+
+	^ tableName
+]
+
+{ #category : 'accessing' }
+DataFrameAbstractSqliteWriter >> tableName: anObject [
+
+	tableName := anObject
+]

src/DataFrame-IO-Sqlite/DataFrameSqliteColumnMappingWriter.class.st

@@ -0,0 +1,56 @@
+Class {
+	#name : 'DataFrameSqliteColumnMappingWriter',
+	#superclass : 'DataFrameAbstractSqliteWriter',
+	#instVars : [
+		'columnMappings'
+	],
+	#category : 'DataFrame-IO-Sqlite',
+	#package : 'DataFrame-IO-Sqlite'
+}
+
+{ #category : 'writing' }
+DataFrameSqliteColumnMappingWriter class >> writeToTable: aString columnMappings: aCollection [
+
+	^ self new
+		  tableName: aString;
+		  columnMappings: aCollection;
+		  yourself
+]
+
+{ #category : 'accessing' }
+DataFrameSqliteColumnMappingWriter >> columnMappings [
+
+	^ columnMappings
+]
+
+{ #category : 'accessing' }
+DataFrameSqliteColumnMappingWriter >> columnMappings: anObject [
+
+	columnMappings := anObject
+]
+
+{ #category : 'writing' }
+DataFrameSqliteColumnMappingWriter >> write: aDataFrame to: aSqliteConnection [
+
+	| fieldIndices args dfCols tblCols stmt nCols |
+	nCols := columnMappings size.
+	dfCols := aDataFrame columnNames.
+	fieldIndices := columnMappings collect: [ :m |
+		                dfCols indexOf: (m isAssociation
+				                 ifTrue: [ m key ]
+				                 ifFalse: [ m ]) ].
+	tblCols := columnMappings collect: [ :m | m value ].
+	args := Array new: fieldIndices size.
+
+	stmt := aSqliteConnection prepare:
+		        (self insertQueryForColumns: tblCols).
+
+	aDataFrame do: [ :r |
+		| row |
+		row := r asArray.
+		1 to: nCols do: [ :i |
+			| rowVal |
+			rowVal := row at: (fieldIndices at: i).
+			args at: i put: rowVal ].
+		stmt execute: args ]
+]

src/DataFrame-IO-Sqlite/DataFrameSqliteWriter.class.st

@@ -1,8 +1,7 @@
 Class {
 	#name : 'DataFrameSqliteWriter',
-	#superclass : 'DataFrameWriter',
+	#superclass : 'DataFrameAbstractSqliteWriter',
 	#instVars : [
-		'tableName',
 		'columnNames'
 	],
 	#category : 'DataFrame-IO-Sqlite',
@@ -48,32 +47,6 @@ DataFrameSqliteWriter >> getColumnNamesFor: aDataFrame [
 	^ columnNames
 ]
 
-{ #category : 'helpers' }
-DataFrameSqliteWriter >> insertQueryForColumns: aSequence [
-	""
-	^ String streamContents: [ :strm |
-		strm
-			nextPutAll: 'INSERT INTO ';
-			nextPutAll: tableName;
-			nextPut: $(;
-			nextPutAll: (',' join: aSequence);
-			nextPutAll: ')VALUES('.
-		aSequence do: [ :ignore | strm nextPut: $? ] separatedBy: [ strm nextPut: $, ].
-		strm nextPut: $) ]
-]
-
-{ #category : 'accessing' }
-DataFrameSqliteWriter >> tableName [
-
-	^ tableName
-]
-
-{ #category : 'accessing' }
-DataFrameSqliteWriter >> tableName: anObject [
-
-	tableName := anObject
-]
-
 { #category : 'writing' }
 DataFrameSqliteWriter >> write: aDataFrame to: aSqliteConnection [