SQL Dialects Reference/Data structure definition/Data types/Character types

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[edit] Character types

This page includes comparison tables which can be big and complex.

While it's perfectly all right to view them in their complete state, it is recommended to install a comparison tables extension that would allow to select particular columns of interest for comparison.

Data type DB2 Firebird Ingres MSSQL MySQL Oracle PostgreSQL SQLite OpenLink Virtuoso Linter
Variable-length with limit VARCHAR(n) VARCHAR(n) VARCHAR(n)
NVARCHAR(n)		 VARCHAR(n)
NVARCHAR(n)		 VARCHAR(n) VARCHAR2(n)
VARCHAR(n) is slated for deprecation		 VARCHAR(n) VARCHAR(n) VARCHAR(n) VARCHAR(n)
NVARCHAR(n)
Fixed-length, blank padded string CHAR(n) CHAR(n) CHAR(n)
NCHAR(n)		 CHAR(n)
NCHAR(n)		 CHAR(n) CHAR(n) CHAR(n) CHAR(n) CHAR(n) CHAR(n)
NCHAR(n)
Text CLOB BLOB SUB_TYPE 1 TEXT,
CLOB,
NCLOB,
LONG VARCHAR,
LONG NVARCHAR		 TEXT / NTEXT
VARCHAR(MAX) / NVARCHAR(MAX) [1]		 TEXT[2] CLOB TEXT TEXT[2] LONG VARCHAR BLOB - the same as long binary objects

Notes:

  1. ↑ The VARCHAR(MAX) / NVARCHAR(MAX) data types are introduced in SQL Server 2005 and allow texts up to 2GB without the programming limitations of the TEXT / NTEXT data types
  2. ↑ a b MySQL and SQLite have several variable character types: TINYTEXT, TEXT, MEDIUMTEXT LONGTEXT
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