Fix #3235: remote metadata is updated instead of delete + insert

CHANGELOG.md

@@ -22,6 +22,7 @@ We refer to [GitHub issues](https://github.com/JabRef/jabref/issues) by using `#
 ### Fixed
  - We fixed an issue where JabRef would not terminated after asking to collect anonymous statistics [#2955 comment](https://github.com/JabRef/jabref/issues/2955#issuecomment-334591123)
  - We fixed an issue where JabRef would not shut down when started with the '-n' (No GUI) option.
+ - We improved the way metadata is updated in remote databases. [#3235](https://github.com/JabRef/jabref/issues/3235)
 
 ### Removed
 

src/main/java/org/jabref/shared/DBMSProcessor.java

@@ -527,23 +527,39 @@ public Map<String, String> getSharedMetaData() {
  * @param data JabRef meta data as map
  */
  public void setSharedMetaData(Map<String, String> data) throws SQLException {
- connection.createStatement().executeUpdate("TRUNCATE TABLE " + escape("METADATA")); // delete data all data from table
-
- for (Map.Entry<String, String> metaEntry : data.entrySet()) {
-
- StringBuilder query = new StringBuilder()
+ StringBuilder updateQuery = new StringBuilder()
+ .append("UPDATE ")
+ .append(escape("METADATA"))
+ .append(" SET ")
+ .append(escape("VALUE"))
+ .append(" = ? ")
+ .append(" WHERE ")
+ .append(escape("KEY"))
+ .append(" = ?");
+
+ StringBuilder insertQuery = new StringBuilder()
  .append("INSERT INTO ")
  .append(escape("METADATA"))
  .append("(")
  .append(escape("KEY"))
  .append(", ")
  .append(escape("VALUE"))
  .append(") VALUES(?, ?)");
-
- try (PreparedStatement preparedStatement = connection.prepareStatement(query.toString())) {
- preparedStatement.setString(1, metaEntry.getKey());
- preparedStatement.setString(2, metaEntry.getValue());
- preparedStatement.executeUpdate();
+
+ for (Map.Entry<String, String> metaEntry : data.entrySet()) {
+ try (PreparedStatement updateStatement = connection.prepareStatement(updateQuery.toString())) {
+ updateStatement.setString(2, metaEntry.getKey());
+ updateStatement.setString(1, metaEntry.getValue());
+ if (updateStatement.executeUpdate() == 0) {
+ // No rows updated -> insert data
+ try (PreparedStatement insertStatement = connection.prepareStatement(insertQuery.toString())) {
+ insertStatement.setString(1, metaEntry.getKey());
+ insertStatement.setString(2, metaEntry.getValue());
+ insertStatement.executeUpdate();
+ } catch (SQLException e) {
+ LOGGER.error("SQL Error: ", e);
+ } 
+ }
  } catch (SQLException e) {
  LOGGER.error("SQL Error: ", e);
  }