Fixed flyway#2341: MySQL: Reset SQL_SAFE_UPDATES and FOREIGN_KEY_CHEC…

…KS after each migration

flyway-core/src/main/java/org/flywaydb/core/internal/database/mysql/MySQLConnection.java

@@ -21,6 +21,7 @@
 import org.flywaydb.core.internal.database.base.Connection;
 import org.flywaydb.core.internal.database.base.Schema;
 import org.flywaydb.core.internal.database.base.Table;
+import org.flywaydb.core.internal.exception.FlywaySqlException;
 import org.flywaydb.core.internal.util.StringUtils;
 
 import java.sql.SQLException;
@@ -36,10 +37,15 @@ public class MySQLConnection extends Connection<MySQLDatabase> {
 
     private static final String USER_VARIABLES_TABLE_MARIADB = "information_schema.user_variables";
     private static final String USER_VARIABLES_TABLE_MYSQL = "performance_schema.user_variables_by_thread";
+    private static final String FOREIGN_KEY_CHECKS = "foreign_key_checks";
+    private static final String SQL_SAFE_UPDATES = "sql_safe_updates";
 
     private final String userVariablesQuery;
     private final boolean canResetUserVariables;
 
+    private final int originalForeignKeyChecks;
+    private final int originalSqlSafeUpdates;
+
     MySQLConnection(Configuration configuration, MySQLDatabase database, java.sql.Connection connection
             , boolean originalAutoCommit
 
@@ -56,6 +62,17 @@ public class MySQLConnection extends Connection<MySQLDatabase> {
                 + (database.isMariaDB() ? USER_VARIABLES_TABLE_MARIADB : USER_VARIABLES_TABLE_MYSQL)
                 + " WHERE variable_value IS NOT NULL";
         canResetUserVariables = hasUserVariableResetCapability();
+
+        originalForeignKeyChecks = getIntVariableValue(FOREIGN_KEY_CHECKS);
+        originalSqlSafeUpdates = getIntVariableValue(SQL_SAFE_UPDATES);
+    }
+
+    private int getIntVariableValue(String varName) {
+        try {
+            return jdbcTemplate.queryForInt("SELECT @@" + varName);
+        } catch (SQLException e) {
+            throw new FlywaySqlException("Unable to determine value for '"+ varName + "' variable", e);
+        }
     }
 
     // #2215: ensure the database is recent enough and the current user has the necessary SELECT grant
@@ -87,6 +104,8 @@ private boolean hasUserVariableResetCapability() {
     @Override
     protected void doRestoreOriginalState() throws SQLException {
         resetUserVariables();
+        jdbcTemplate.execute("SET " + FOREIGN_KEY_CHECKS + "=?, " + SQL_SAFE_UPDATES + "=?",
+                originalForeignKeyChecks, originalSqlSafeUpdates);
     }
 
     // #2197: prevent user-defined variables from leaking beyond the scope of a migration