From a Sybase Database, how I can get table description ( field names and types)?

爷,独闯天下 提交于 2019-11-28 03:16:28
Lukasz Lysik

Check sysobjects and syscolumns tables.

Here is a diagram of Sybase system tables.

List of all user tables:

SELECT * FROM sysobjects WHERE type = 'U'

You can change 'U' to other objects:

  • C – computed column
  • D – default
  • F – SQLJ function
  • L – log
  • N – partition condition
  • P – Transact-SQL or SQLJ procedure
  • PR – prepare objects (created by Dynamic SQL)
  • R – rule
  • RI – referential constraint
  • S – system table
  • TR – trigger
  • U – user table
  • V – view
  • XP – extended stored procedure

List of columns in a table:

SELECT sc.* 
FROM syscolumns sc
INNER JOIN sysobjects so ON sc.id = so.id
WHERE so.name = 'my_table_name'

sp_help is what you're looking for.

From Sybase online documentation on the sp_help system procedure:

Description

Reports information about a database object (any object listed in sysobjects) and about system or user-defined datatypes, as well as computed columns and function-based indexes. Column displays optimistic_index_lock.

Syntax

sp_help [objname]

[...]

Here is the (partial) output for the publishers table (pasted from Using sp_help on database objects):

Name               Owner        Object_type     Create_date 
----------------   -----------  -------------   ------------------------------
publishers         dbo          user table      Nov 9 2004 9:57AM

(1 row affected)
Column_name Type     Length   Prec  Scale   Nulls   Default_name   Rule_name
----------- -------  ------   ----- ------- ------- -------------- ---------- 
pub_id      char          4    NULL  NULL        0  NULL           pub_idrule
pub_name    varchar      40    NULL  NULL        1  NULL           NULL
city        varchar      20    NULL  NULL        1  NULL           NULL
state       char          2    NULL  NULL        1  NULL           NULL
Access_Rule_name    Computed_Column_object     Identity
------------------- -------------------------  ------------
NULL                NULL                                  0
NULL                NULL                                  0
NULL                NULL                                  0
NULL                NULL                                  0

Still quoting Using sp_help on database objects:

If you execute sp_help without supplying an object name, the resulting report shows each object in sysobjects, along with its name, owner, and object type. Also shown is each user-defined datatype in systypes and its name, storage type, length, whether null values are allowed, and any defaults or rules bound to it. The report also notes if any primary or foreign key columns have been defined for a table or view.

Sybase IQ:

describe table_name;
     SELECT
DB_NAME() TABLE_CATALOG,
NULL TABLE_SCHEMA,
so.name TABLE_NAME,
sc.name COLUMN_NAME,
sc.colid ORDINAL_POSITION,
NULL COLUMN_DEFAULT,
CASE WHEN st.allownulls=1 THEN 'YES'
 ELSE 'NO'
END IS_NULLABLE,
st.name DATA_TYPE,
CASE WHEN st.name like '%char%' THEN st.length
END CHARACTER_MAXIMUM_LENGTH,
CASE WHEN st.name like '%char%' THEN st.length
END*2 CHARACTER_OCTET_LENGTH,
CASE WHEN st.name in ('numeric','int') THEN st.length
END NUMERIC_MAXIMUM_LENGTH,
CASE WHEN st.name in ('numeric','int') THEN st.prec
END NUMERIC_PRECISION,
NULL NUMERIC_PRECISION_RADIX,
CASE WHEN st.name in ('numeric','int') THEN st.scale
END NUMERIC_SCALE,
CASE WHEN st.name in ('datetime') THEN st.prec
END DATETIME_PRECISION,
NULL CHARACTER_SET_CATALOG,
NULL CHARACTER_SET_SCHEMA,
NULL COLLATION_CATALOG,
NULL COLLATION_SCHEMA,
NULL DOMAIN_CATALOG,
NULL DOMAIN_SCHEMA,
NULL DOMAIN_NAME
FROM 
sysobjects so
INNER JOIN 
syscolumns sc
ON sc.id = so.id
inner join systypes st on st.usertype = sc.usertype 
WHERE so.name = 'TableName'

You can search for column in all tables in database using:

SELECT so.name 
FROM sysobjects so
INNER JOIN syscolumns sc ON so.id = sc.id 
WHERE sc.name = 'YOUR_COLUMN_NAME'

sp_tables will also work in isql. It gives you the list of tables in the current database.

When finding user table, in case if want the table owner name also, you can use the following:

select su.name + '.' + so.name
from   sysobjects so,
       sysusers   su
where  so.type = 'U' and
       so.uid  = su.uid
order  by su.name,
          so.name

If you want to use a command line program, but are not restricted to using SQL, you can use SchemaCrawler. SchemaCrawler is open source, and can produce files in plain text, CSV, or (X)HTML formats.

Here a different approach to get meta data. This very helpful SQL command returns you the table / view definition as text:

SELECT text FROM syscomments WHERE id = OBJECT_ID('MySchema.MyTable') ORDER BY number, colid2, colid

Enjoy Patrick

In the Sybase version I use, the following gives list of columns for selected table

select *
FROM sys.syscolumns sc
where tname = 'YOUR_TABLE_NAME'
--and creator='YOUR_USER_NAME' --if you want to further restrict tables
--according to the user name that created it

For Sybase ASE, sp_columns table_name will return all the table metadata you are looking for.

If Sybase is SQL-92 compliant then this information is stored within the INFORMATION_SCHEMA tables.

So the following will give you a list of tables and views in any SQL-92 compliant database

SELECT TABLE_NAME
FROM INFORMATION_SCHEMA.TABLES
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