Max(ID) of each table on a database - sql

Question

I am trying to get the maximum value MAX(ID) for each table I have which contains ID on my DB "Table_Example" and one schema_name in specific.
A single example:
SELECT MAX(ID) FROM Schema_name.Table_name1
This retrieve the maximum ID value that is located on Table_name1, but I have 84 tables. I would like to know the max of each table only in one column.
This is the code where I am working on currently:
I am using information_schema.columns to get the names of the tables automatic and the schema each table belongs to in order to get the whole DB IDs max(id) in one column.
USE TABLE_EXAMPLE
GO
DECLARE #ID NVARCHAR(MAX) --int
SET #ID = (SELECT DISTINCT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'SCHEMA_NAME' AND COLUMN_NAME IN ('ID') AND DATA_TYPE = 'INT')
SELECT #ID FROM (SELECT ('SCHEMA_NAME'+'.'+TABLE_NAME) AS TABLE_NAME FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'SCHEMA_NAME' AND COLUMN_NAME = 'ID' AND DATA_TYPE='INT') AS W
This Script retrieve wrong data but I think I am a bit closed to get the values, but I am not sure what I am doing wrong.
Could someone give me any good approach? Or any better option to get it done?

Answer 1

If you are wanting the max value in your identity columns, regardless of the names of those columns, then this is a very simple way of doing it. This will give you the Table Name, the name of the Identity Column, and the max value of that column:
SELECT sys.tables.name AS [Table Name],
sys.identity_columns.name AS [Column Name],
last_value AS [Last Value]
FROM sys.identity_columns
INNER JOIN sys.tables
ON sys.identity_columns.object_id = sys.tables.object_id
ORDER BY last_value DESC

Answer 2

This enumerate all tables with column Id and MAX value of this ID:
DECLARE #query nvarchar(MAX);
SELECT #query = COALESCE(#query + char(10)+'UNION ALL '+char(10)+'SELECT '''+QUOTENAME(s.name)+'.'+QUOTENAME(T.name)+''' [Table], MAX(Id) [Max] FROM '+QUOTENAME(s.name)+'.'+QUOTENAME(T.name),
'SELECT '''+QUOTENAME(s.name)+'.'+QUOTENAME(T.name)+''' [Table], MAX(Id) [Max] FROM '+QUOTENAME(s.name)+'.'+QUOTENAME(T.name))
FROM sys.schemas S
JOIN sys.tables T ON S.schema_id=T.schema_id
JOIN sys.columns C ON T.object_id=C.object_id
WHERE C.name='Id';
EXEC(#query);

Answer 3

Try like this,
This would give you the script.
SELECT DISTINCT 'SELECT MAX(' + + COLUMN_NAME + ') as ' + table_name + 'MaxId FROM ' + table_name
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_SCHEMA = 'dbo'
AND COLUMN_NAME IN ('ID')

Answer 4

CREATE TABLE #MaxValues (SchemaName SYSNAME , TableName SYSNAME , MaxID INT)
GO
Declare #SchemaName SYSNAME = 'dbo' --<-- Pass you schema name to this variable
,#ColumnName SYSNAME = 'ID' --<-- Column Name
,#DataType SYSNAME = 'INT' --<-- Data type
DECLARE #TableName SYSNAME , #SchmaName SYSNAME
, #Sql NVARCHAR(MAX) , #ColName SYSNAME;
Declare Cur CURSOR LOCAL FAST_FORWARD FOR
SELECT s.name , t.name , c.name
FROM sys.columns c
Inner join sys.tables t on c.object_id = t.object_id
Inner join sys.schemas s on s.schema_id = t.schema_id
Inner join sys.types tp on tp.user_type_id = c.user_type_id
WHERE s.name = #SchemaName
AND c.name = #ColumnName
AND tp.name = #DataType
OPEN Cur
FETCH NEXT FROM Cur INTO #SchmaName , #TableName , #ColName
WHILE (##FETCH_STATUS =0)
BEGIN
SET #Sql = N'INSERT INTO #MaxValues (SchemaName, TableName, MaxID )'
+ N' SELECT #SchmaName ,#TableName, MAX(' + QUOTENAME(#ColName) + N') '
+ N' FROM ' + QUOTENAME(#SchmaName) + '.' + QUOTENAME(#TableName)
Exec sp_executesql #Sql
,N'#SchmaName SYSNAME , #TableName SYSNAME'
,#SchmaName
,#TableName
FETCH NEXT FROM Cur INTO #SchmaName , #TableName , #ColName
END
CLOSE Cur
DEALLOCATE Cur
SELECT * FROM #MaxValues

Answer 5

Perhaps a little dynamic SQL
Edit This will return the Table Name(s) and Max ID in one dataset
Declare #SQL varchar(max) = '>>>'
Select #SQL = #SQL + SQL
From (
Select SQL='Union All Select TableName='''+concat('[',Table_Schema,'].[',Table_Name,']')+''',MaxID=max(ID) From '+concat('[',Table_Schema,'].[',Table_Name,'] ')
From INFORMATION_SCHEMA.COLUMNS
Where Column_Name = 'ID'
) A
Set #SQL=Replace(#SQL,'>>>Union All ','')
Exec(#SQL)

Answer 6

This script will list all the max ids. It is assuming your first column is the ID, regardless of its name.
DECLARE #Script AS VARCHAR(MAX) = ''
SELECT #Script = #Script + 'SELECT MAX(' + COLUMN_NAME + ') AS ID FROM ' + c.TABLE_NAME + ' UNION ALL ' + CHAR(13)+CHAR(10)
FROM INFORMATION_SCHEMA.COLUMNS c
INNER JOIN INFORMATION_SCHEMA.TABLES t ON c.TABLE_NAME = t.TABLE_NAME
WHERE c.ORDINAL_POSITION = 1 and t.TABLE_TYPE = 'BASE TABLE' and c.TABLE_SCHEMA = 'dbo' and c.DATA_TYPE = 'int'
SELECT #Script = LEFT(#Script, LEN(#Script) - 12)
EXEC (#Script)