Hello,

I am new to Firebird, I have experience using MS SQL. I am trying to
convert some code that performs various checks but having problems with
the syntax. One thing I need to convert is SQL to detect whether a
table exists.

I have tried these in Squirrel and isql connected to an embedded db
version Firebird 2.5

I tried the following

SELECT RDB$RELATION_NAME FROM RDB$RELATIONS
WHERE RDB$RELATION_NAME = 'SCHEMA_VERSION'

works fine. I went on to:

select case when exists(SELECT RDB$RELATION_NAME FROM RDB$RELATIONS
WHERE RDB$RELATION_NAME = 'SCHEMA_VERSION') then 1 else 0 end;

Error: GDS Exception. 335544569. Dynamic SQL Error
SQL error code = -104
Unexpected end of command - line 2, column 62
SQLState: 42000
ErrorCode: 335544569

I thought maybe firebird wants named result so I tried

select (case when exists(SELECT RDB$RELATION_NAME FROM RDB$RELATIONS
WHERE RDB$RELATION_NAME = 'SCHEMA_VERSION') then 1 else 0 end) as
result;

Error: GDS Exception. 335544569. Dynamic SQL Error
SQL error code = -104
Unexpected end of command - line 2, column 70
SQLState: 42000
ErrorCode: 335544569

I am now down to some very basic queries that work in MS SQL but not in
firebird:

SELECT CASE
WHEN 4 = 5 THEN 1
WHEN 5 = 6 THEN 2
ELSE 0
END;

Error: GDS Exception. 335544569. Dynamic SQL Error
SQL error code = -104
Unexpected end of command - line 5, column 2
SQLState: 42000
ErrorCode: 335544569

or

SELECT (CASE
WHEN 4 = 5 THEN 1
WHEN 5 = 6 THEN 2
ELSE 0
END) as result;

Error: GDS Exception. 335544569. Dynamic SQL Error
SQL error code = -104
Unexpected end of command - line 5, column 10
SQLState: 42000
ErrorCode: 335544569

I have looked at the following documentation but I don't see what I am
doing wrong

http://www.firebirdsql.org/file/documentation/reference_manuals/reference_material/html/langrefupd25.html


thank you for any help you can give,

Jim s