[sql] Find the number of columns in a table

It is possible to find the number of rows in a table:

select count(*) from tablename

Is it possible to find the number of columns in a table?

Query to count the number of columns in a table:

select count(*) from user_tab_columns where table_name = 'tablename';

Replace tablename with the name of the table whose total number of columns you want returned.

SELECT count(*) FROM information_schema.`COLUMNS` C
WHERE table_name = 'your_table_name'
AND TABLE_SCHEMA = "your_db_name"

SELECT COUNT(*)
  FROM INFORMATION_SCHEMA.COLUMNS
 WHERE table_catalog = 'database_name' -- the database
   AND table_name = 'table_name'

Following query finds how columns in table:-

 SELECT COUNT(COLUMN_NAME) FROM USER_TAB_COLUMNS
 WHERE TABLE_NAME = 'TableName';

SELECT count(*)
FROM information_schema.columns
WHERE table_name = 'Your_table_name';

Note: Your_table_name should be replaced by your actual table name

db2 'describe table "SCHEMA_NAME"."TBL_NAME"'

Since all answers are using COUNT(), you can also use MAX() to get the number of columns in a specific table as

SELECT MAX(ORDINAL_POSITION) NumberOfColumnsInTable
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_CATALOG = 'YourDatabaseNameHere'
      AND 
      TABLE_SCHEMA = 'YourSchemaNameHere'
      AND
      TABLE_NAME = 'YourTableNameHere';

See The INFORMATION_SCHEMA COLUMNS Table

It is possible to find the number of columns in a table just by using 3 simple lines of PHP code.

$sql="SELECT * FROM table";
$query=mysqli_query($connect_dude,$sql);    
$num=mysqli_num_fields($query);

$num would return the number of columns on a given table in this case.

Hopefully,it would help others.

It's working (mysql) :

SELECT TABLE_NAME , count(COLUMN_NAME)
FROM information_schema.columns
GROUP BY TABLE_NAME 

SELECT COUNT(COLUMN_NAME) FROM INFORMATION_SCHEMA.COLUMNS WHERE 
TABLE_CATALOG = 'database_name' AND TABLE_SCHEMA = 'dbo'
AND TABLE_NAME = 'table_name'

Its been little late but please take it from me...

In the editor(New Query) by select the database object it can be a table too, if we use the Shortcut Key Alt+F1 we will get all the information of the object and I think will solve your problem as well.

SELECT COUNT(*) 
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE 
   TABLE_NAME = 'table_name';

Or use the sys.columns

--SQL 2005
SELECT  *
FROM    sys.columns
WHERE   OBJECT_NAME(object_id) = 'spt_values'
-- returns 6 rows = 6 columns

--SQL 2000
SELECT  *
FROM    syscolumns
WHERE   OBJECT_NAME(id) = 'spt_values'
-- returns 6 rows = 6 columns

SELECT  *
FROM    dbo.spt_values
    -- 6 columns indeed

SELECT TABLE_SCHEMA
    , TABLE_NAME
    , number = COUNT(*) 
FROM INFORMATION_SCHEMA.COLUMNS
GROUP BY TABLE_SCHEMA, TABLE_NAME;

This one worked for me.

Here is how you can get a number of table columns using Python 3, sqlite3 and pragma statement:

con = sqlite3.connect(":memory:")    
con.execute("CREATE TABLE tablename (d1 VARCHAR, d2 VARCHAR)")
cur = con.cursor()
cur.execute("PRAGMA table_info(tablename)")
print(len(cur.fetchall()))

Source

Well I tried Nathan Koop's answer and it didn't work for me. I changed it to the following and it did work:

SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_name = 'table_name'

It also didn't work if I put USE 'database_name' nor WHERE table_catalog = 'database_name' AND table_name' = 'table_name'. I actually will be happy to know why.

A MySQL answer adapted slightly from the MSDN example for MySqlDataReader.GetValues:

//assumes you've already created a connection, opened it, 
//and executed a query to a reader

while(reader.Read())
{
    Object[] values = new Object[reader.FieldCount];
    int fieldCount = reader.GetValues(values);

    Console.WriteLine("\nreader.GetValues retrieved {0} columns.",   fieldCount);
    for (int i = 0; i < fieldCount; i++)
        Console.WriteLine(values[i]);
}

Using MySqlDataReader.FieldCount will allow you to retrieve the number of columns in the row you've queried.

Using JDBC in Java:

    String quer="SELECT * FROM sample2 where 1=2";
    
    Statement st=con.createStatement();
    ResultSet rs=st.executeQuery(quer);
    ResultSetMetaData rsmd = rs.getMetaData();
    int NumOfCol=0;
    NumOfCol=rsmd.getColumnCount();
    System.out.println("Query Executed!! No of Colm="+NumOfCol);

Can get using following sql statement:

select count(*) Noofcolumns from SYSCOLUMNS where id=(select id from SYSOBJECTS where name='table_name')

SELECT COUNT(COLUMN_NAME) 
FROM INFORMATION_SCHEMA.COLUMNS 
WHERE 
    TABLE_CATALOG = 'Database name' 
    AND TABLE_SCHEMA = 'dbo' 
    AND TABLE_NAME = 'table name'