jackcess delete row and set autoincrement column

问题

How delete row from table with help jackcess? I try so, but it's bad:

    Table ptabl = db.getTable("person");
    int pcount = ptabl.getRowCount();
    for (int i = 0; i < pcount; i++) {
        Map<String, Object> row2 = ptabl.getNextRow();
        if (row2.get("id") == Integer.valueOf(1)) {
            ptabl.deleteCurrentRow();
        }
    }

How set column "id" attribute to autoincrement?

Table newTable = new TableBuilder("diagnosis"). addColumn(new ColumnBuilder("id") .setSQLType(Types.INTEGER) .toColumn()) .addColumn(new ColumnBuilder("name") .setSQLType(Types.VARCHAR) .toColumn()).toTable(db);

回答1:

If your id column is indexed, you can use an IndexCursor to quickly find columns:

IndexCursor cursor = new CursorBuilder(ptabl).setIndexByColumnNames("id").toIndexCursor();
if(cursor.findFirstRowByEntry(1)) {
  cursor.deleteCurrentRow();
}

If your id column is not indexed, you can use a normal cursor, which is more convenient but effectively no faster than your current code (just does a table scan):

Cursor cursor = new CursorBuilder(ptab1).toCursor();
Column idCol = ptab1.getColumn("id");
if(cursor.findFirstRow(idCol, 1)) {
  cursor.deleteCurrentRow();
}

And your own answer indicates you already figured out how to make a column auto increment.

回答2:

For set autoincrement to column:

Table newTable = new TableBuilder("diagnosis").addColumn(new ColumnBuilder("id").setAutoNumber(true).setSQLType(Types.INTEGER).toColumn()).addColumn(new ColumnBuilder("name").setSQLType(Types.VARCHAR).toColumn()).toTable(db);

来源：https://stackoverflow.com/questions/9343470/jackcess-delete-row-and-set-autoincrement-column

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jackcess