Create test data in SQL Server

Question

Does anyone have or know of a SQL script that will generate test data for a given table?

Ideally it will look at the schema of the table and create row(s) with test data

Answer 1

Have you tried ApexSQL Generate: https://www.apexsql.com/sql_tools_generate.aspx ?

I stumbled upon it during my own search for the similar thing, and it did the job quite well. It’s not free, but you get a free trial with all features available, so you can try before you buy.

I think it will suite your needs quite well, since it keeps track of your relations between tables, column types and even constraints (for a more complex databases).

One thing I liked (and needed, actually) was that it has built-in values for actual names, addresses etc. It helps so much when querying created test data and not get a random strings.

Also, you can export to SQL (or few other formats) and use the created data at any time to repopulate the database.

Answer 2

We need step by step create query for tables need entry data. i used below codes, step by step for insert test data:

1. Create a table :

CREATE TABLE dbo.TestTableSize
(
    MyKeyField VARCHAR(10) NOT NULL,
    MyDate1 DATETIME NOT NULL,
    MyDate2 DATETIME NOT NULL,
    MyDate3 DATETIME NOT NULL,
    MyDate4 DATETIME NOT NULL,
    MyDate5 DATETIME NOT NULL
)

2. Variable Declarations

DECLARE @RowCount INT
DECLARE @RowString VARCHAR(10)
DECLARE @Random INT
DECLARE @Upper INT
DECLARE @Lower INT
DECLARE @InsertDate DATETIME

3.Set on time :

SET @Lower = -730
SET @Upper = -1
SET @RowCount = 0

4.Populate the Table :

WHILE @RowCount < 3000000
BEGIN

5.Preparing Values

SET @RowString = CAST(@RowCount AS VARCHAR(10))

    SELECT @Random = ROUND(((@Upper - @Lower -1) * RAND() + @Lower), 0)

    SET @InsertDate = DATEADD(dd, @Random, GETDATE())

6. Write insert statment :

INSERT INTO TestTableSize
        (MyKeyField
        ,MyDate1
        ,MyDate2
        ,MyDate3
        ,MyDate4
        ,MyDate5)
    VALUES
        (REPLICATE('0', 10 - DATALENGTH(@RowString)) + @RowString
        , @InsertDate
        ,DATEADD(dd, 1, @InsertDate)
        ,DATEADD(dd, 2, @InsertDate)
        ,DATEADD(dd, 3, @InsertDate)
        ,DATEADD(dd, 4, @InsertDate))

    SET @RowCount = @RowCount + 1
END

7. Complete code :

DECLARE @RowCount INT
DECLARE @RowString VARCHAR(10)
DECLARE @Random INT
DECLARE @Upper INT
DECLARE @Lower INT
DECLARE @InsertDate DATETIME

SET @Lower = -730
SET @Upper = -1
SET @RowCount = 0

WHILE @RowCount < 3000000
BEGIN
    SET @RowString = CAST(@RowCount AS VARCHAR(10))
    SELECT @Random = ROUND(((@Upper - @Lower -1) * RAND() + @Lower), 0)
    SET @InsertDate = DATEADD(dd, @Random, GETDATE())

    INSERT INTO TestTableSize
        (MyKeyField
        ,MyDate1
        ,MyDate2
        ,MyDate3
        ,MyDate4
        ,MyDate5)
    VALUES
        (REPLICATE('0', 10 - DATALENGTH(@RowString)) + @RowString
        , @InsertDate
        ,DATEADD(dd, 1, @InsertDate)
        ,DATEADD(dd, 2, @InsertDate)
        ,DATEADD(dd, 3, @InsertDate)
        ,DATEADD(dd, 4, @InsertDate))

    SET @RowCount = @RowCount + 1
END

Answer 3

Well I thought I would pull my finger out and write myself a light weight data generator:

declare @select varchar(max), @insert varchar(max), @column varchar(100),
    @type varchar(100), @identity bit, @db nvarchar(100)

set @db = N'Orders'
set @select = 'select '
set @insert = 'insert into ' + @db + ' ('


declare crD cursor fast_forward for
select column_name, data_type, 
COLUMNPROPERTY(
    OBJECT_ID(
       TABLE_SCHEMA + '.' + TABLE_NAME), 
    COLUMN_NAME, 'IsIdentity') AS COLUMN_ID
from Northwind.INFORMATION_SCHEMA.COLUMNS
where table_name = @db


open crD
fetch crD into @column, @type, @identity

while @@fetch_status = 0
begin
if @identity = 0 or @identity is null
begin
    set @insert = @insert + @column + ', ' 
    set @select = @select  + 
        case @type
            when 'int' then '1'
            when 'varchar' then '''test'''
            when 'nvarchar' then '''test'''
            when 'smalldatetime' then 'getdate()'
            when 'bit' then '0'
            else 'NULL'
        end + ', ' 
end
fetch crD into @column, @type, @identity
end 

set @select = left(@select, len(@select) - 1)
set @insert = left(@insert, len(@insert) - 1) + ')'
exec(@insert + @select)

close crD
deallocate crD

Given any table, the script will create one record with some arbitrary values for the types; int, varchar, nvarchar, smalldatetime and bit. The case statement could be replaced with a function. It won't travel down dependencies but it will skip any seeded columns.

My motivation for creating this is to test my NHibernate mapping files against a table with some 50 columns so I was after a quick a simple script which can be re-used.

Answer 4

There is a program from red gate software which will do this for you. It's called SQL Data Generator.

Answer 5

Some flavours of Visual Studio have data generation built in. If you use database projects in it you can create data generation plans. Here's the MSDN article

Answer 6

I used following way it basically copies data from itself , the data grows exponentially with every execution.Claveat is that You have to have some sample data at first and also you have to execute the query eg I had 327680 rows of data when i started with 10 rows of data .by executing the query just 16 times.Execute one more time and i will hage 655360 rows of data!

 insert into mytable select [col1], [col2], [col3] from mytable