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package org.jooq.impl;

// ...
import static org.jooq.impl.Keywords.K_MINUS;

import org.jooq.Keyword;
import org.jooq.SQLDialect;
import org.jooq.Select;

A combine operator is used to combine result sets of two arbitrary Select queries. 
Author:
Lukas Eder/**
 * A combine operator is used to combine result sets of two arbitrary
 * {@link Select} queries.
 *
 * @author Lukas Eder
 */
enum CombineOperator {

    
Unite the sets of rows produced by the two Select's (disallowing duplicate records). /**
     * Unite the sets of rows produced by the two {@link Select}'s (disallowing
     * duplicate records).
     */
    UNION("union"),

    
Unite the bags of rows produced by the two Select's (allowing duplicate records). /**
     * Unite the bags of rows produced by the two {@link Select}'s (allowing
     * duplicate records).
     */
    UNION_ALL("union all"),

    
Remove all rows in the set of rows produced by the second Select from the set of rows produced by the first Select (disallowing duplicate records). /**
     * Remove all rows in the set of rows produced by the second {@link Select}
     * from the set of rows produced by the first {@link Select} (disallowing
     * duplicate records).
     */
    EXCEPT("except"),

    
Remove all rows in the bag of rows produced by the second Select from the bag of rows produced by the first Select (allowing duplicate records). /**
     * Remove all rows in the bag of rows produced by the second {@link Select}
     * from the bag of rows produced by the first {@link Select} (allowing
     * duplicate records).
     */
    EXCEPT_ALL("except all"),

    
Retain all rows in the sets of rows produced by both Select's (disallowing duplicate records). /**
     * Retain all rows in the sets of rows produced by both {@link Select}'s
     * (disallowing duplicate records).
     */
    INTERSECT("intersect"),

    
Retain all rows in the bags of rows produced by both Select's (allowing duplicate records). /**
     * Retain all rows in the bags of rows produced by both {@link Select}'s
     * (allowing duplicate records).
     */
    INTERSECT_ALL("intersect all");

    private final String  sql;
    private final Keyword keyword;

    private CombineOperator(String sql) {
        this.sql = sql;
        this.keyword = DSL.keyword(sql);
    }

    public final String toSQL(SQLDialect dialect) {





        return sql;
    }

    public final Keyword toKeyword(SQLDialect dialect) {





        return keyword;
    }
}