I'm trying to create a stored procedure (or a a trigger, function, anything) to check if all the tables in a database is accessible.
My idea is to get all the tables in database, and then try to acess them with a simple select, if this succeeds for all the tables, everything is supposed to be ok.
I couldn't think of anything else to solve this problem, but I don't know how to do this, or all this intead.
1 - to get all the tables name I did:
SELECT RDB$RELATION_NAME TABLE
FROM RDB$RELATIONS
WHERE RDB$VIEW_BLR IS NULL
AND (RDB$SYSTEM_FLAG IS NULL OR RDB$SYSTEM_FLAG = 0)
ORDER BY TABLE
Now I just need to create the SELECT statement to each table, and run a query:
SELECT FIRST 1 * FROM [TABLE];
while it's ok, it continues, if all the tables are accessible, my database is ok.
Can anybody help me with this? Is this the correct aproach to solve this problem?
As a_horse_with_no_name commented, this is really strange request... if you see the table in the RDB$RELATIONS you can be pretty sure the table exists in the database. If the table is listed in the DB metadata but actually doesn't exist then the DB is corrupted and your idea to use select to check it's "accessibilty" is pointless... Also, the table might be there but the user might not have select right for it, IOW you need to take the user rights into account too.
Anyway, you can use the EXECUTE STATEMENT to execute dynamically built DSQL statement, something like
declare stmt varchar(1024);
declare ctab varchar(31);
BEGIN
FOR SELECT RDB$RELATION_NAME
FROM RDB$RELATIONS
WHERE RDB$VIEW_BLR IS NULL AND (RDB$SYSTEM_FLAG IS NULL OR RDB$SYSTEM_FLAG = 0)
INTO :ctab DO BEGIN
stmt = 'select ... from ' || ctab;
execute statement stmt;
END;
END
To check is the database corrupted you should use the gfix utility with -validate option.
Related
EDIT: The things I've tried below came directly from the alleged duplicate. The solutions actually do work fine with a user defined sp (and probably most system sp's), but for whatever reason it doesn't work with this one.
I can run exec sp_showpendingchanges on the distribution publication database without any issues. However I want to capture the results in a table
I've tried:
SELECT * INTO #tmpTable
FROM OPENROWSET('SQLNCLI', 'Server=SERVER; Trusted_Connection=yes;',
'EXEC sp_showpendingchanges')
and:
SELECT * INTO #tmpTable
FROM OPENQUERY(SERVER, 'exec sp_showpendingchanges')
Both of these statements return an error that says: Invalid object name 'sysmergepublications'.
I tried to specify the initial catalog in the connection string and even tried adding a USE statement in the last parameter of each statement (i.e. I used an embedded EXEC statement with double-single quotes and all that). But I still end up with the same error.
So how can I get the results from exec sp_showpendingchanges into a temporary table, and preferably without having to define the table myself? If all else fails I will make a program in C#, but really hoping there's a simpler way to just do this with just SQL.
Here is a working example
You create a table
DECLARE #result_table TABLE
(
destination_server SYSNAME ,
pub_name SYSNAME ,
destination_db_name SYSNAME ,
is_dest_subscriber BIT ,
article_name SYSNAME ,
pending_deletes INT ,
pending_ins_and_upd INT
)
execute the script
INSERT INTO #result_table
EXEC sp_showpendingchanges
view the results
SELECT * FROM #result_table
I read your question but definetly cannot understand what the problem to create temp table. Anyway, if you can execute SP but get an error when you do it through linkedserver or openrowset - than problem is in permissions.
Check permissions on sysmergepublications table. If user, which you use for linked server or openrowset, has no grant on do select this table you need to add this permission to user.
I hope it will help you.
I'm trying to write a small script to create a database if it doesn't exist, and create a table for that database if the table doesn't exist. What I have is this:
IF (db_id('db') is null) BEGIN
print 'Must create the database!';
CREATE DATABASE db;
END
USE db;
IF (object_id('test_table', 'U') is null) BEGIN
print 'Must create the table!';
CREATE TABLE test_table (
id int
);
END
I'm getting a strange error with this:
Database 'db' does not exist. Make sure that the name is entered correctly.
I'm guessing that it's parsing the script before running it and finding that 'db' doesn't exist, so it can't use it.
There must be a solution to this. Any help is appreciated.
SOLVED!
I realised 5 minutes after posting that the GO keyword solves the problem. Here is the fixed code:
IF (db_id('db') is null) BEGIN
print 'Must create the database!'
CREATE DATABASE db;
END
GO
USE db
IF (object_id('test_table', 'U') is null) BEGIN
print 'Must create the table!';
CREATE TABLE test_table (
id int
);
END
Sorry for wasting everyone's time.
SQL statements are parsed as one batch unless you break them apart. In SQL Server, you can use GO to do this. In both MySQL and SQL Server, you can use BEGIN and END.
If you want to commit the separate blocks to the database in different instances you can use BEGIN TRANS / COMMIT TRANS and START TRANSACTION / COMMIT for SQL Server and MySQL, respectively.
Something along the lines of Check if table exists in SQL Server would probably work (With a slight change)
IF (NOT EXISTS (SELECT *
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'TheSchema'
AND TABLE_NAME = 'TheTable'))
BEGIN
--Do Stuff
END
I might suggest using the built-in SQL syntax -
CREATE DATABASE name IF NOT EXISTS;
And subsequently
CREATE TABLE name(definition) IF NOT EXISTS;
I have a select statement that needs to look up a customer ID from a customer name. If an ID does not exist for that name, a new record needs to be created in the customer table. this has to be done as part of a select statement (related to the app its being run from).
I tried looking at a UDF that returned either the existing ID or a new ID, before realizing that you can't modify tables from a function.
any idea how to accomplish this?
EDIT:
I think i need to clarify things a bit more. The select statement can and will change on a per-implementation basis. What I'm looking for is a generic way of looking up or creating the customer id (that table and the need to do the lookup does not change) as part of a larger select statement.
the app that is using the sql loads the select statement from a config file, and has 'SELECT' hard coded, so there's no chance of adding an exec before the select etc.
It looks like what I need is something like 'select a.1 (exec dotheLookup(name)) as customerID, a.2 FROM table, but I'm not sure how to go about that.
I suggest you to Create a stored procedure for this. Something like
Create procedure customer
--parameters
AS
Begin
IF exists(Select lookup(customerName) as customerID from table)
BEGIN
--Your select goes here
END
ELSE
BEGIN
--Insert into customer table and return scopeidentity
--Select goes here
END
END
Updated Answer:
You cannot perform data manipulation using select statement.
You could execute a stored procedure before you execute the SELECT statement, the run a function that returns ID from name:
exec CheckForCustomerByNameAndAddIDIfItDoesntExist(customerName)
declare iCustomerID int
select iCustomerID = GetCustomerIDFromName(customerName)
select a.1, a.2, iCustomerID as customerID from table
Something like that
Can you modify the database server? If so, add a linked server pointing to the local server.
EXEC master.dbo.sp_addlinkedserver #server = N'LinkedLocal', #srvproduct=N'', #provider=N'SQLNCLI', #datasrc=N'LocalServerName'
EXEC master.dbo.sp_addlinkedsrvlogin #rmtsrvname=N'LinkedLocal',#useself=N'True',#locallogin=NULL,#rmtuser=NULL,#rmtpassword=NULL
Then just run an OPENQUERY that invokes a stored procedure that does your work:
select * from OPENQUERY("LinkedLocal", 'exec Database.Schema.StoredProcedure ''Param1'', ''Param2'')
I got a bit of a problem with a Oracle query
create or replace
PROCEDURE "LOAD_USERNAME"
IS
cursor usu is
select userid
from local_user;
BEGIN
for usu_rec in usu
loop
update loc_user set username =(
select cod_user
from (
select cod_user, row_number() over (order by date_createad desc) r
from user_table#DBLINK where cod_person=usu_rec.userid
)
where r = 1
)
where externaluserid=usu_rec.userid;
end loop;
END;
Basically, trying to get code of a user(last one created) from other database and update a local table. This seems to work but I takes too much time. I can only check the remote database through a DBLINK.
Please, I want some help for a better way to do this.
I thank your help in advance.
You want to minimise the number of times you go over the network. So you should join to the remote table in your driving cursor and pull the username back there. This will be better as that query is only executed once (indexing/design will determine how well it goes). But your updates will then only be working with local data.
Edit: Removed my PL/SQL as #Aitor's was better
As Sodved said, is better to had the join in your cursor. You can try something like this:
create or replace
PROCEDURE "LOAD_USERNAME"
IS
cursor usu is
select distinct local_user.userid,your_dblink_table.cod_user
from local_user, user_table#bdlink your_dblink_table
where local_user.userid=your_dblink_table.codperson
and local_user.externaluserid=local_user.userid;
BEGIN
for usu_rec in usu
loop
update loc_user set username =usu_rec.cod_user
where externauserid=usu_rec.userid;
end loop;
commit;
END;
If you have to load massive updates, you can try a bulk collect/for all approach in the cursor.
Oracle has provided built-in functionality for this sort of thing for several major versions. If you're on an older database you should use replication. In more recent versions this has been deprecated in favour of Streams.
I'm after a simple stored procedure to drop tables. Here's my first attempt:
CREATE PROC bsp_susf_DeleteTable (#TableName char)
AS
IF EXISTS (SELECT name FROM sysobjects WHERE name = #TableName)
BEGIN
DROP TABLE #TableName
END
When I parse this in MS Query Analyser I get the following error:
Server: Msg 170, Level 15, State 1, Procedure bsp_susf_DeleteTable, Line 6
Line 6: Incorrect syntax near '#TableName'.
Which kind of makes sense because the normal SQL for a single table would be:
IF EXISTS (SELECT name FROM sysobjects WHERE name = 'tbl_XYZ')
BEGIN
DROP TABLE tbl_XYZ
END
Note the first instance of tbl_XYZ (in the WHERE clause) has single quotes around it, while the second instance in the DROP statement does not. If I use a variable (#TableName) then I don't get to make this distinction.
So can a stored procedure be created to do this? Or do I have to copy the IF EXISTS ... everywhere?
You should be able to use dynamic sql:
declare #sql varchar(max)
if exists (select name from sysobjects where name = #TableName)
BEGIN
set #sql = 'drop table ' + #TableName
exec(#sql)
END
Hope this helps.
Update: Yes, you could make #sql smaller, this was just a quick example. Also note other comments about SQL Injection Attacks
Personally I would be very wary of doing this. If you feel you need it for administrative purposes, please make sure the rights to execute this are extremely limited. Further, I would have the proc copy the table name and the date and the user executing it to a logging table. That way at least you will know who dropped the wrong table. You may want other protections as well. For instance you may want to specify certain tables that cannot be dropped ever using this proc.
Further this will not work on all tables in all cases. You cannot drop a table that has a foreign key associated with it.
Under no circumstances would I allow a user or anyone not the database admin to execute this proc. If you havea a system design where users can drop tables, there is most likely something drastically wrong with your design and it should be rethought.
Also, do not use this proc unless you have a really, really good backup schedule in place and experience restoring from backups.
You'll have to use EXEC to execute that query as a string. In other words, when you pass in the table name, define a varchar and assign the query and tablename, then exec the variable you created.
Edit: HOWEVER, I don't recommend that because someone could pass in sql rather than a TableName and cause all kinds of wonderful problems. See Sql injection for more information.
Your best bet is to create a parameterized query on the client side for this. For example, in C# I would do something like:
// EDIT 2: on second thought, ignore this code; it probably won't work
SqlCommand sc = new SqlCommand();
sc.Connection = someConnection;
sc.CommandType = Command.Text;
sc.CommandText = "drop table #tablename";
sc.Parameters.AddWithValue("#tablename", "the_table_name");
sc.ExecuteNonQuery();