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Light wrapper of JDBC, support ddl, dml, query, plsql/procedure/function, transaction and manage sql file.

There is a newer version: 9.0.2

package com.github.chengyuxing.sql.page.impl;

import com.github.chengyuxing.sql.Args;
import com.github.chengyuxing.sql.page.PageHelper;
import org.jetbrains.annotations.NotNull;

/**
 * Oracle page helper, e.g.
 * 
 * select *
 * from (select t.*, rownum {@link #ROW_NUM_KEY}
 *       from (...) t
 *       where rownum <= :{@link #END_NUM_KEY})
 *  where {@link #ROW_NUM_KEY} >= :{@link  #START_NUM_KEY}
 * 
 *
 * @see #pagedArgs()
 */
public class OraclePageHelper extends PageHelper {
    public int end() {
        int end = pageNumber * pageSize;
        if (end > recordCount)
            end = recordCount;
        return end;
    }

    public int start() {
        return (pageNumber - 1) * pageSize + 1;
    }

    @Override
    public @NotNull String pagedSql(char namedParamPrefix, @NotNull String sql) {
        return "select *\n" +
                "from (select t.*, rownum " + ROW_NUM_KEY + "\n" +
                "          from (" + sql + ") t\n" +
                "          where rownum <= " + namedParamPrefix + END_NUM_KEY + ")\n" +
                " where " + ROW_NUM_KEY + " >= " + namedParamPrefix + START_NUM_KEY;
    }

    @Override
    public @NotNull Args pagedArgs() {
        return Args.of(START_NUM_KEY, start()).add(END_NUM_KEY, end());
    }
}