UCanAccess Exception UCAExc:::3.0.0 needs column or cannot drop sole column of table - ucanaccess

Question

I am attempting to use UCanAccess to build a program to help me script some Access Database queries. Ultimately I want daily reports generated from a cron job. My couple of test cases to connect to said database give the following exception: UCAExc:::3.0.0 needs column or cannot drop sole column of table.
I'm a dabbler in databases, and this database is maintained by some other part of the company's organization.
The exception is thrown on the getConnection call.
Output of console.sh after compact and repair: Cannot execute:CREATE
CACHED TABLE EMPL() needs column or cannot drop sole column of table
Loaded Tables:
Loaded Queries:
Loaded Indexes:
net.ucanaccess.jdbc.UcanaccessSQLException: UCAExc:::3.0.0 needs
column or cannot drop sole column of table at
net.ucanaccess.jdbc.UcanaccessDriver.connect(UcanaccessDriver.java:258)
at java.sql.DriverManager.getConnection(DriverManager.java:571) at
java.sql.DriverManager.getConnection(DriverManager.java:187) at
net.ucanaccess.console.Main.main(Main.java:145) Caused by:
java.sql.SQLSyntaxErrorException: needs column or cannot drop sole
column of table at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown
Source) at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source) at
org.hsqldb.jdbc.JDBCStatement.fetchResult(Unknown Source) at
org.hsqldb.jdbc.JDBCStatement.executeUpdate(Unknown Source) at
net.ucanaccess.converters.LoadJet.exec(LoadJet.java:1416) at
net.ucanaccess.converters.LoadJet.access$000(LoadJet.java:71) at
net.ucanaccess.converters.LoadJet$TablesLoader.createSyncrTable(LoadJet.java:481)
at
net.ucanaccess.converters.LoadJet$TablesLoader.createSyncrTable(LoadJet.java:411)
at
net.ucanaccess.converters.LoadJet$TablesLoader.createTable(LoadJet.java:807)
at
net.ucanaccess.converters.LoadJet$TablesLoader.createTable(LoadJet.java:761)
at
net.ucanaccess.converters.LoadJet$TablesLoader.createTables(LoadJet.java:942)
at
net.ucanaccess.converters.LoadJet$TablesLoader.loadTables(LoadJet.java:1036)
at
net.ucanaccess.converters.LoadJet$TablesLoader.access$2900(LoadJet.java:273)
at net.ucanaccess.converters.LoadJet.loadDB(LoadJet.java:1479) at
net.ucanaccess.jdbc.UcanaccessDriver.connect(UcanaccessDriver.java:243)
... 3 more Caused by: org.hsqldb.HsqlException: needs column or
cannot drop sole column of table at
org.hsqldb.error.Error.error(Unknown Source) at
org.hsqldb.error.Error.error(Unknown Source) at
org.hsqldb.ParserDDL.compileCreateTableBody(Unknown Source) at
org.hsqldb.ParserDDL.compileCreateTable(Unknown Source) at
org.hsqldb.ParserDDL.compileCreate(Unknown Source) at
org.hsqldb.ParserCommand.compilePart(Unknown Source) at
org.hsqldb.ParserCommand.compileStatements(Unknown Source) at
org.hsqldb.Session.executeDirectStatement(Unknown Source) at
org.hsqldb.Session.execute(Unknown Source) ... 16 more UCAExc:::3.0.0
needs column or cannot drop sole column of table

Answer 1

UCanAccess will throw an exception when opening a database if it contains a table with no columns defined.
A table with no columns is not a valid table. Access itself will not allow us to save such a table ...
... however it is possible to make such a table using DDL as in the following VBScript
Option Explicit
Dim con
Set con = CreateObject("ADODB.Connection")
con.Open "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\__tmp\31886535.accdb"
On Error Resume Next
con.Execute "DROP TABLE BadTable"
On Error Goto 0
con.Execute "CREATE TABLE BadTable (foo INT)"
con.Execute "ALTER TABLE BadTable DROP COLUMN foo"
con.Close
To avoid the error when opening the database with UCanAccess, simply open the database in Access and delete the table that has no columns defined.