The correct solution is: SELECT o.* FROM `Persons` o # ‘o’ from ‘oldest person in group’ LEFT JOIN `Persons` b # ‘b’ from ‘bigger age’ ON o.Group = b.Group AND o.Age < b.Age WHERE b.Age is NULL # bigger age not found How it works: It matches each row from o with all the rows … Read more
For SQL Server 2008: Convert(date, getdate()) Please refer to https://docs.microsoft.com/en-us/sql/t-sql/functions/getdate-transact-sql
Stored procedures are a batch of SQL statements that can be executed in a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples. … Read more
I realize this has already been marked as answered, but we used to do it like this: IF NOT EXISTS (SELECT * FROM sys.objects WHERE type=”P” AND OBJECT_ID = OBJECT_ID(‘dbo.MyProc’)) exec(‘CREATE PROCEDURE [dbo].[MyProc] AS BEGIN SET NOCOUNT ON; END’) GO ALTER PROCEDURE [dbo].[MyProc] AS …. Just to avoid dropping the procedure.
Postgres 15 or newer Postgres 15 (currently beta) adds the clause NULLS NOT DISTINCT. The release notes: Allow unique constraints and indexes to treat NULL values as not distinct (Peter Eisentraut) Previously NULL values were always indexed as distinct values, but this can now be changed by creating constraints and indexes using UNIQUE NULLS NOT … Read more
Here’s some test sql for all the styles. DECLARE @now datetime SET @now = GETDATE() select convert(nvarchar(MAX), @now, 0) as output, 0 as style union select convert(nvarchar(MAX), @now, 1), 1 union select convert(nvarchar(MAX), @now, 2), 2 union select convert(nvarchar(MAX), @now, 3), 3 union select convert(nvarchar(MAX), @now, 4), 4 union select convert(nvarchar(MAX), @now, 5), 5 union … Read more
Three tables (one for storing all items, one for all tags, and one for the relation between the two), properly indexed, with foreign keys set running on a proper database, should work well and scale properly. Table: Item Columns: ItemID, Title, Content Table: Tag Columns: TagID, Title Table: ItemTag Columns: ItemID, TagID
As described in Cast Functions and Operators: The type for the result can be one of the following values: BINARY[(N)] CHAR[(N)] DATE DATETIME DECIMAL[(M[,D])] SIGNED [INTEGER] TIME UNSIGNED [INTEGER] Therefore, you should use: SELECT CAST(PROD_CODE AS UNSIGNED) FROM PRODUCT
A REGEXP might be more efficient, but you’d have to benchmark it to be sure, e.g. SELECT * from fiberbox where field REGEXP ‘1740|1938|1940’;
Read committed is an isolation level that guarantees that any data read was committed at the moment is read. It simply restricts the reader from seeing any intermediate, uncommitted, ‘dirty’ read. It makes no promise whatsoever that if the transaction re-issues the read, will find the Same data, data is free to change after it … Read more