revert unnecessary changes

Author: vincentlauvlwj

ktorm-support-sqlite/src/main/kotlin/org/ktorm/support/sqlite/Functions.kt

@@ -192,7 +192,7 @@ public fun ColumnDeclaring<String>.instr(right: ColumnDeclaring<String>): Functi
  * SQLite instr function, translated to `instr(left, right)`.
  */
 public fun ColumnDeclaring<String>.instr(right: String): FunctionExpression<Int> {
-    return instr(wrapArgument(right))
+    return this.instr(wrapArgument(right))
 }
 
 /**

ktorm-support-sqlite/src/main/kotlin/org/ktorm/support/sqlite/SQLiteDialect.kt

@@ -79,34 +79,6 @@ public open class SQLiteFormatter(
         _parameters += ArgumentExpression(expr.limit ?: Int.MAX_VALUE, IntSqlType)
     }
 
-    override fun visitUnion(expr: UnionExpression): UnionExpression {
-        when (expr.left) {
-            is SelectExpression -> visitQuery(expr.left)
-            is UnionExpression -> visitUnion(expr.left as UnionExpression)
-        }
-
-        if (expr.isUnionAll) {
-            writeKeyword("union all ")
-        } else {
-            writeKeyword("union ")
-        }
-
-        when (expr.right) {
-            is SelectExpression -> visitQuery(expr.right)
-            is UnionExpression -> visitUnion(expr.right as UnionExpression)
-        }
-
-        if (expr.orderBy.isNotEmpty()) {
-            newLine(Indentation.SAME)
-            writeKeyword("order by ")
-            visitOrderByList(expr.orderBy)
-        }
-        if (expr.offset != null || expr.limit != null) {
-            writePagination(expr)
-        }
-        return expr
-    }
-
     protected open fun visitInsertOrUpdate(expr: InsertOrUpdateExpression): InsertOrUpdateExpression {
         writeKeyword("insert into ")
         visitTable(expr.table)
@@ -118,16 +90,16 @@ public open class SQLiteFormatter(
             writeKeyword("on conflict ")
             writeInsertColumnNames(expr.conflictColumns)
 
-            if (expr.updateAssignments.isNotEmpty()) {
+            if (expr.updateAssignments.isEmpty()) {
+                writeKeyword("do nothing ")
+            } else {
                 writeKeyword("do update set ")
                 visitColumnAssignments(expr.updateAssignments)
 
                 if (expr.where != null) {
                     writeKeyword("where ")
                     visit(expr.where)
                 }
-            } else {
-                writeKeyword("do nothing ")
             }
         }
 
@@ -152,16 +124,16 @@ public open class SQLiteFormatter(
             writeKeyword("on conflict ")
             writeInsertColumnNames(expr.conflictColumns)
 
-            if (expr.updateAssignments.isNotEmpty()) {
+            if (expr.updateAssignments.isEmpty()) {
+                writeKeyword("do nothing ")
+            } else {
                 writeKeyword("do update set ")
                 visitColumnAssignments(expr.updateAssignments)
 
                 if (expr.where != null) {
                     writeKeyword("where ")
                     visit(expr.where)
                 }
-            } else {
-                writeKeyword("do nothing ")
             }
         }