DBDropForeignKeys.java

/*
 * Copyright 2023 Gregory Graham.
 *
 * Commercial licenses are available, please contact info@gregs.co.nz for details.
 * 
 * This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. 
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 * or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
 * 
 * You are free to:
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 * 
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package nz.co.gregs.dbvolution.actions;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import nz.co.gregs.dbvolution.DBRow;
import nz.co.gregs.dbvolution.databases.DBDatabase;
import nz.co.gregs.dbvolution.databases.QueryIntention;
import nz.co.gregs.dbvolution.databases.definitions.DBDefinition;
import nz.co.gregs.dbvolution.exceptions.AccidentalBlankQueryException;
import nz.co.gregs.dbvolution.exceptions.UnableToInstantiateDBRowSubclassException;
import nz.co.gregs.dbvolution.utility.StringCheck;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 *
 * @author gregorygraham
 */
public class DBDropForeignKeys extends DBAction {

	private static final long serialVersionUID = 1L;
	private static final Log LOG = LogFactory.getLog(DBDropForeignKeys.class);

	public <R extends DBRow> DBDropForeignKeys(DBRow table) {
		super(table, QueryIntention.DROP_FOREIGN_KEYS);
	}

	@Override
	protected DBActionList getRevertDBActionList() {
		DBActionList reverts = new DBActionList();
		reverts.add(new DBCreateForeignKeys(getRow()));
		return reverts;
	}

	@Override
	public List<String> getSQLStatements(DBDatabase db) {
		List<String> fkClauses = new ArrayList<>(0);
		DBDefinition definition = db.getDefinition();
		if (definition.supportsAlterTableAddConstraint()) {
			DBRow table = getRow();
			var fields = table.getColumnPropertyWrappers();
			for (var field : fields) {
				if (field.isColumn() && !field.getQueryableDatatype().hasColumnExpression()) {
					final String fkSQL = definition.getAlterTableDropForeignKeyStatement(table, field);
					if (StringCheck.isNotEmptyNorNull(fkSQL)) {
						fkClauses.add(fkSQL);
					}
				}
			}
		}
		return fkClauses;
	}

	@Override
	public DBActionList execute(DBDatabase db) throws SQLException {
		return execute2(db);
	}

	@Override
	protected DBActionList prepareActionList(DBDatabase db) throws AccidentalBlankQueryException, SQLException, UnableToInstantiateDBRowSubclassException {
		final DBDropForeignKeys newAction = new DBDropForeignKeys(getRow());
		DBActionList actions = new DBActionList(newAction);
		return actions;
	}

	@Override
	protected void prepareRollbackData(DBDatabase db, DBActionList actions) {	
	}
}