How do I create a stored procedure that will optionally search columns?

Question

I\'m working on an application for work that is going to query our employee database. The end users want the ability to search based on the standard name/department criteria

Answer 1

Write a procedure to insert all employee data whose name start with A in table??

Answer 2

We can use Generic @Search Parameter and pass any value to it for searching.

GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author: --
-- Create date:
-- Description: --
-- =============================================
CREATE PROCEDURE [dbo].[usp_StudentList]
    @PageNumber INT    = 1, -- Paging parameter
    @PageSize   INT    = 10,-- Paging parameter
    @Search  VARCHAR(MAX) = NULL, --Generic Search Parameter
    @OrderBy VARCHAR(MAX) = 'FirstName', --Default Column Name 'FirstName' for records ordering
    @SortDir VARCHAR(MAX) = 'asc' --Default ordering 'asc' for records ordering
AS
BEGIN
    SET NOCOUNT ON;

    --Query required for paging, this query used to show total records
    SELECT COUNT(StudentId) AS RecordsTotal FROM Student

    SELECT Student.*, 
        --Query required for paging, this query used to show total records filtered
        COUNT(StudentId) OVER (PARTITION BY 1) AS RecordsFiltered 
    FROM Student
    WHERE 
    --Generic Search 
    -- Below is the column list to add in Generic Serach
    (@Search IS NULL OR Student.FirstName LIKE '%'+ @Search +'%')
    OR (@Search IS NULL OR Student.LastName LIKE '%'+ @Search +'%')
    --Order BY
    -- Below is the column list to allow sorting
    ORDER BY 
    CASE WHEN @SortDir = 'asc' AND @OrderBy = 'FirstName' THEN Student.FirstName END,
    CASE WHEN @SortDir = 'desc' AND @OrderBy = 'FirstName' THEN Student.FirstName  END DESC,
    CASE WHEN @SortDir = 'asc' AND @OrderBy = 'LastName' THEN Student.LastName END,
    CASE WHEN @SortDir = 'desc' AND @OrderBy = 'LastName' THEN Student.LastName  END DESC,
    OFFSET @PageSize * (@PageNumber - 1) ROWS FETCH NEXT @PageSize ROWS ONLY;
END

Answer 3

I would stick with the NULL/COALESCE method over AdHoc Queries, and then test to make sure you don't have performance problems.

If it turns out that you have slow running queries because it's doing a table scan when you're searching on columns that are indexed, you could always supplement the generic search stored procedure with additional specific ones that allow searching on these indexed fields. For instance, you could have a special SP that does searches by CustomerID, or Last/First Name.

Answer 4

My first thought was to write a query something like this...

SELECT EmpId, NameLast, NameMiddle, NameFirst, DepartmentName
  FROM dbo.Employee
       INNER JOIN dbo.Department ON dbo.Employee.DeptId = dbo.Department.Id
 WHERE IdCrq IS NOT NULL
       AND
       (
          @bitSearchFirstName = 0
          OR
          Employee.NameFirst = @vchFirstName
       )
       AND
       (
          @bitSearchMiddleName = 0
          OR
          Employee.NameMiddle = @vchMiddleName
       )
       AND
       (
          @bitSearchFirstName = 0
          OR
          Employee.NameLast = @vchLastName
       )
       AND
       (
          @bitSearchDepartment = 0
          OR
          Department.Id = @intDeptID
       )

...which would then have the caller provide a bit flag if they want to search a particular field and then supply the value if they are to search for it, but I don't know if this is creating a sloppy WHERE clause or if I can get away with a CASE statement in the WHERE clause.

As you can see this particular code is in T-SQL, but I'll gladly look at some PL-SQL / MySQL code as well and adapt accordingly.