Set Limit for a Table Rows in SQL

Set Limit for a Table Rows In SQL

Create an AFTER INSERT trigger on the table. Here's something that would be relatively effective with your requirement:

create trigger LimitTable
on YourTableToLimit
after insert
as
    declare @tableCount int
    select @tableCount = Count(*)
    from YourTableToLimit

    if @tableCount > 50
    begin
        rollback
    end
go

How To Set Limit Table Row SQL?

One thing that i can assure you..

1. Create a trigger that if > 100 then delete first record record.

see here as your guide.

How to limit number of rows can be store in mysql table?

I think there is no such inbuilt functionality providede by MySQL. One solution is that you can create trigger.

CREATE TRIGGER your_trigger_name
BEFORE INSERT ON your_table_name
FOR EACH ROW
BEGIN
    DECLARE cnt INT;

    SELECT count(*) INTO cnt FROM your_table_name;

    IF cnt = 10 THEN
        SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT = 'You can store only 10 records.';
    END IF;
END;

Try above trigger on your table. Replace your table_name with your_table_name.

Hope this will help you.

SQL query with limit on rows from one table, not the result set

SELECT t3.a, t2.b FROM (SELECT * FROM t1 LIMIT 5) t3
LEFT JOIN t2 ON ...

Note that if you use limit without an 'order by' clause, it is not defined which 5 rows you will get. Consider adding an 'order by' clause if this is not what you want.

How can I set a maximum number of rows in MySQL table?

Try to make a restriction on adding a new record to a table. Raise an error when a new record is going to be added.

DELIMITER $$

CREATE TRIGGER trigger1
BEFORE INSERT
ON table1
FOR EACH ROW
BEGIN
  SELECT COUNT(*) INTO @cnt FROM table1;
  IF @cnt >= 25 THEN
    CALL sth(); -- raise an error
  END IF;
END
$$

DELIMITER ;

Note, that COUNT operation may be slow on big InnoDb tables.

On MySQL 5.5 you can use SIGNAL // RESIGNAL statement to raise an error.

Limit row a table in SQL and Insert new rows on Top

You can't really limit a table for a fix number of records but you can get rid of unwanted records. Assuming you are on SQL-Server

--STEP1 :Do your insert here

--STEP2: Delete older records over 200 ordering by dateTime column
;WITH CTE AS (

  SELECT *, ROW_NUMBER() OVER (ORDER BY DateTime DESC) rn 
  FROM YourTable
)
DELETE CTE WHERE rn > 200

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