denodo SQL Type Mapping

denodo 7.0 saves some manual coding when building the ‘Base Views’ by performing some initial data type conversions from ANSI SQL type to denodo Virtual DataPort data types. So, where is a quick reference mapping to show to what the denodo Virtual DataPort Data Type mappings are:

ANSI SQL types To Virtual DataPort Data types Mapping

ANSI SQL TypeVirtual DataPort Type
BIT (n)blob
BIT VARYING (n)blob
BOOLboolean
BYTEAblob
CHAR (n)text
CHARACTER (n)text
CHARACTER VARYING (n)text
DATElocaldate
DECIMALdouble
DECIMAL (n)double
DECIMAL (n, m)double
DOUBLE PRECISIONdouble
FLOATfloat
FLOAT4float
FLOAT8double
INT2int
INT4int
INT8long
INTEGERint
NCHAR (n)text
NUMERICdouble
NUMERIC (n)double
NUMERIC (n, m)double
NVARCHAR (n)text
REALfloat
SMALLINTint
TEXTtext
TIMESTAMPtimestamp
TIMESTAMP WITH TIME ZONEtimestamptz
TIMESTAMPTZtimestamptz
TIMEtime
TIMETZtime
VARBITblob
VARCHARtext
VARCHAR ( MAX )text
VARCHAR (n)text

ANSI SQL Type Conversion Notes

  • The function CAST truncates the output when converting a value to a text, when these two conditions are met:
  1. You specify a SQL type with a length for the target data type. E.g. VARCHAR(20).
  2. And, this length is lower than the length of the input value.
  • When casting a boolean to an integertrue is mapped to 1 and false to 0.

Related References

denodo 7.0 Type Conversion Functions

Oracle Express Edition Error – ORA-65096: invalid common user or role name

While trying to create user in Oracle Database 18c Express Edition I kept getting an “ORA-65096: invalid common user or role name” error, which didn’t make sense to me so after validating my command, that I was signed in as an admin user, and determining that my “CREATE USER” was formatted correctly.  I did some additional research and determined that in the hidden parameter “_ORACLE_SCRIPT” needed to be set to “True” starting with the Oracle Version 12c and higher.

Setting the “_ORACLE_SCRIPT” values

To set the “_ORACLE_SCRIPT” hidden variable to “True” you need to run an “Alter” command. Then you will be able to create the desired user and run your grants commands as usual.

Alter SQL Command

alter session set “_oracle_script”=true;

How to Determine Your Oracle Database Name

Oracle provides a few ways to determine which database you are working in.  Admittedly, I usually know which database I’m working in, but recently I did an Oracle Database Express Edition (XE) install which did not goes has expected and I had reason to confirm which database I was actually in when the SQL*Plus session opened.  So, this lead me to consider how one would prove exactly which database they were connected to.  As it happens, Oracle has a few ways to quickly display which database you are connected to and here are two easy ways to find out your Oracle database name in SQL*Plus:

  • V$DATABASE
  • GLOBAL_NAME

Checking the GLOBAL_NAME table

The First method is to run a quick-select against the GLOBAL_NAME table, which. is publicly available to logged-in users of the database

Example GLOBAL_NAME Select Statement

select * from global_name;

Checking the V$DATABASE Variable

The second method is to run a quick-select a V$database. However, not everyone will have access to the V$database variable.

Example V$database Select Statement

select name from V$database;