java.sql.SQLException: Database not selected yet.
    at com.informix.util.IfxErrMsg.getSQLException(IfxErrMsg.java:408)
    at com.informix.jdbc.IfxSqli.a(IfxSqli.java:3461)
    at com.informix.jdbc.IfxSqli.E(IfxSqli.java:3774)
    at com.informix.jdbc.IfxSqli.dispatchMsg(IfxSqli.java:2580)
    at com.informix.jdbc.IfxSqli.receiveMessage(IfxSqli.java:2496)
    at com.informix.jdbc.IfxSqli.executeStatementQuery(IfxSqli.java:1662)
    at com.informix.jdbc.IfxSqli.executeStatementQuery(IfxSqli.java:1635)
    at com.informix.jdbc.IfxResultSet.a(IfxResultSet.java:206)
    at com.informix.jdbc.IfxStatement.executeQueryImpl(IfxStatement.java:1229)
    at com.informix.jdbc.IfxStatement.executeQuery(IfxStatement.java:219)
    at \\...\\ .\\हिñçêČάй語简�?한\\.Zꇶꄯꇔᜧ finally.a(Unknown Source)
    at \\...\\ .\\हिñçêČάй語简�?한\\.Zꇶꄯꇔᜧ finally.a(Unknown Source)
    at \\...\\ .\\हिñçêČάй語简�?한\\.Zꇶꄯꇔᜧ finally.a(Unknown Source)
    at com.aquafold.aquaeditor.sql.SQLStdCompletionQuery.queryCompletionOnType(Unknown Source)
    at \\...\\ .\\हिñçêČάй語简�?한\\.Z̪ꑞ⡭ꐉ interface.query(Unknown Source)
    at org.netbeans.spi.editor.completion.support.AsyncCompletionTask.run(AsyncCompletionTask.java:218)
    at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:572)
    at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:997)
Caused by: java.sql.SQLException
    at com.informix.util.IfxErrMsg.getSQLException(IfxErrMsg.java:408)
    at com.informix.jdbc.IfxSqli.E(IfxSqli.java:3779)
    ... 15 more

also autocompletion not working for sysmaster

DirConnectionNode.getDatabase() for that server reports "ol_w2ksrv37" or "ol_w2ksrv37/sysmaster", instead of "sysmaster".

see QueryAnalyzer : 182

The code won't work until ConnectionProperties.getDatabase() returns the database name instead of an instance (?) name or instance/database combo.

Reassinging to Niels.

Please code review SVN# 20369 :

    public String getDatabase()
    {
        // Comment by Niels : We have reached the top node of a server registration, so there is no database context
        // and thus we return "null" to indicate no database context.  But, in the case of Informix we need to force
        // a database context because Informix is the only vendor which have an unset database context on the server.
        // By returning "sysmaster" for Informix, we force the Query Window to initialize the database context to
        // sysmaster.
        if(cp != null)
        {
            if ( cp.isInformix() )
            {
                return "sysmaster";
            }
            else
            {
                // Comment by Niels : Yes, this is "null" to tell the Query Window not to initialize the database context.
                return null;
            }
        }
        return null;
    }

This is a scary change - but it seems to work.  I am afraid it will backfire somewhere else later.

But fixes the current issue.

this looks good to me.

Andy, it is broken.  Lets discuss.

1. to reproduce: set up an informix server with Instance/database XX/demo.

2. double click on the server node to open a query window - the database is demo (correct)

3. drag the server node to the shortcut toolbar. 

4. click on the shortcut - the database is sysmaster (incorrect).

Reworked this code again.  Please re-test all the possible scenarios (#5544).

This occurs when you kill ADS from Task Manager

Scenario 7 in 5544 for informix doesnt work
Tests for 4 query window with Shortcut + Change Database + Save window
1. Create Shortcut for 4 database in informix server
2. Open the 4 different shortcuts and then change all 4 dropdowns to the same database
3. Kill ADS from task manager and restart
4. When ADS restarts it doesnt save the changed Database

The last comment is an unrelated issue. 

Added saving tabs on user changing current database from the query panel pulldown.