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  • Hmm, why finding by '2' or '2' return the same record?

    - by SXLee
    Hi everyone, forget my newbie question, but why finding by '2' or '2' in Mysql returns the same record? For example: Say I have a record with string field named 'slug', and the value is '2'. And the following SQLs returns same record. SELECT * From articles WHERE slug='2' SELECT * From articles WHERE slug='2'

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  • Does the optimizer filter subqueries with outer where clauses

    - by Mongus Pong
    Take the following query: select * from ( select a, b from c UNION select a, b from d ) where a = 'mung' Will the optimizer generally work out that I am filtering a on the value 'mung' and consequently filter mung on each of the queries in the subquery. OR will it run each query within the subquery union and return the results to the outer query for filtering (as the query would perhaps suggest) In which case the following query would perform better : select * from ( select a, b from c where a = 'mung' UNION select a, b from d where a = 'mung' ) Obviously query 1 is best for maintenance, but is it sacrificing much performace for this? Which is best?

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  • Active Record/ORM vs Normal Forms?

    - by Arsenal
    Hello, I've been playing around with Active Record a bit, and I have noticed that A.C./ORM always uses the following database model when creating a one-to-one relationship Person id | country_id | name | ... Country id | tld | name | ... No I wondered, isn't this a violiation of the third Normal Form? This clearly states "Every non-prime attribute is non-transitively dependent on every key of the table". Well this country_id isn't dependent of personid is it? So is this wrong or am I just not getting the point?

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  • ora-00939 error in reporting services, SSRS

    - by san
    Hi, I have an SSRS report , Oracle is my backend and am using this following query for dataset of my second parameter. select distinct X from v_stf_sec_user_staffing_center usc where usc.center_group_id in ( select distinct center_group_id from V_T_STAFFING_CENTER_GROUP scg where INSTR(','||REPLACE(:PI_REGION_LIST,' ')||',', ','||scg.group_abbreviation||',') 0) and usc.nt_user_name=:PI_NT_USER_NAME Here PI_REGION_LIST is a multivalued parameter of string type. and PI_NT_USER_NAME is a default string valued parameter this query works fine when i try to execute in manulally in the Data tab , also in the Oracle tool. But when i run the report in SSRS and select more than 3 values for the parameter PI_REGION_LIST the report throws an error on this dataset, ora-00939 error,too many arguments for function. I am not able to figure out the error here. Please help me with an idea. Thanks in advance, Suni.

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  • Precision of Interval for PL/SQL Function value

    - by Gary
    Generally, when you specify a function the scale/precision/size of the return datatype is undefined. For example, you say FUNCTION show_price RETURN NUMBER or FUNCTION show_name RETURN VARCHAR2. You are not allowed to have FUNCTION show_price RETURN NUMBER(10,2) or FUNCTION show_name RETURN VARCHAR2(20), and the function return value is unrestricted. This is documented functionality. Now, I get an precision error (ORA-01873) if I push 9999 hours (about 400 days) into the following. The limit is because the default days precision is 2 DECLARE v_int INTERVAL DAY (4) TO SECOND(0); FUNCTION hhmm_to_interval return INTERVAL DAY TO SECOND IS v_hhmm INTERVAL DAY (4) TO SECOND(0); BEGIN v_hhmm := to_dsinterval('PT9999H'); RETURN v_hhmm; -- END hhmm_to_interval; BEGIN v_int := hhmm_to_interval; end; / and it won't allow the precision to be specified directly as part of the datatype returned by the function. DECLARE v_int INTERVAL DAY (4) TO SECOND(0); FUNCTION hhmm_to_interval return INTERVAL DAY (4) TO SECOND IS v_hhmm INTERVAL DAY (4) TO SECOND(0); BEGIN v_hhmm := to_dsinterval('PT9999H'); RETURN v_hhmm; -- END hhmm_to_interval; BEGIN v_int := hhmm_to_interval; end; / I can use a SUBTYPE DECLARE subtype t_int is INTERVAL DAY (4) TO SECOND(0); v_int INTERVAL DAY (4) TO SECOND(0); FUNCTION hhmm_to_interval return t_int IS v_hhmm INTERVAL DAY (4) TO SECOND(0); BEGIN v_hhmm := to_dsinterval('PT9999H'); RETURN v_hhmm; -- END hhmm_to_interval; BEGIN v_int := hhmm_to_interval; end; / Any drawbacks to the subtype approach ? Any alternatives (eg some place to change a default precision) ? Working with 10gR2.

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  • How to use a getter with a nullable?

    - by Desmond Lost
    I am reading a bunch of queries from a database. I had an issue with the queries not closing, so I added a CommandTimeout. Now, the individual queries read from the config file each time they are run. How would I make the code cache the int from the config file only once using a static nullable and getter. I was thinking of doing something along the lines of: static int? var; get{ var = null; if (var.HasValue) ...(i dont know how to complete the rest) My actual code: private object ExecuteQuery(string dbConnStr, bool fixIt) { object result = false; using (SqlConnection connection = new SqlConnection(dbConnStr)) { connection.Open(); using (SqlCommand sqlCmd = new SqlCommand()) { AddSQLParms(sqlCmd); sqlCmd.CommandTimeout = 30; sqlCmd.CommandText = _cmdText; sqlCmd.Connection = connection; sqlCmd.CommandType = System.Data.CommandType.Text; sqlCmd.ExecuteNonQuery(); } connection.Close(); } return result; }}

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  • What is the best way to return result from business layer to presentation layer when using linq - I

    - by samsur
    I have a business layer that has DTOs that are used in the presentation layer. This application uses entity framework. Here is an example of a class called RoleDTO public class RoleDTO { public Guid RoleId { get; set; } public string RoleName { get; set; } public string RoleDescription { get; set; } public int? OrganizationId { get; set; } } In the BLL I want to have a method that returns a list of DTO.. I would like to know which is the better approach: returning IQueryable or list of DTOs. Although i feel that returning Iqueryable is not a good idea because the connection needs to be open. Here are the 2 different methods using the different approaches public class RoleBLL { private servicedeskEntities sde; public RoleBLL() { sde = new servicedeskEntities(); } public IQueryable<RoleDTO> GetAllRoles() { IQueryable<RoleDTO> role = from r in sde.Roles select new RoleDTO() { RoleId = r.RoleID, RoleName = r.RoleName, RoleDescription = r.RoleDescription, OrganizationId = r.OrganizationId }; return role; } Note: in the above method the datacontext is a private attribute and set in the constructor, so that the connection stays opened. Second approach public static List GetAllRoles() { List roleDTO = new List(); using (servicedeskEntities sde = new servicedeskEntities()) { var roles = from pri in sde.Roles select new { pri.RoleID, pri.RoleName, pri.RoleDescription }; //Add the role entites to the DTO list and return. This is necessary as anonymous types can be returned acrosss methods foreach (var item in roles) { RoleDTO roleItem = new RoleDTO(); roleItem.RoleId = item.RoleID; roleItem.RoleDescription = item.RoleDescription; roleItem.RoleName = item.RoleName; roleDTO.Add(roleItem); } return roleDTO; } Please let me know, if there is a better approach - Thanks,

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  • TSQL: grouping customer orders by week

    - by fishhead
    I have a table with a collection of orders. The fields are: customerName (text) DateOfOrder (datetime). I would like to show totals of orders per week per customer. I would like to have it arranged for the Friday of each week so that it looks like this: all dates follow mm/dd/yyyy "bobs pizza", 3/5/2010, 10 "the phone co",3/5/2010,5 "bobs pizza", 3/12/2010, 3 "the phone co",3/12/2010,11 Could somebody please show me how to do this? Thanks

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  • Oracle database connection string PLSQL compatibility

    - by user521180
    Hi I'm using an application called Logi info. it requires a connection string to my oracle database. the connection works fine but in order to configure the connection to recive ref cursors from the database, I apparently need to add PLSQLRSet=1 to the end of the string. when I do that I recieve an error "invalid connection string" Here is my connection string without plsqlrset=1 Data Source=SID; User Id=username; Password=password; My concern is that PLSQLRSet=1 might be .NET paramater only. Can anyone shed some light on the issue. Thanks

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  • SqlServer2008 + expensive union

    - by Tim Mahy
    Hi al, we have 5 tables over which we should query with user search input throughout a stored procedure. We do a union of the similar data inside a view. Because of this the view can not be materialized. We are not able to change these 5 tables drastically (like creating a 6th table that contains the similar data of the 5 tables and reference that new one from the 5 tables). The query is rather expensive / slow what are our other options? It's allowed to think outside the box. Unfortunately I cannot give more information like the table/view/SP definition because of customer confidentiality... greetings, Tim

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  • Tentative date casting in tsql

    - by Tewr
    I am looking for something like TRYCAST in TSQL or an equivalent method / hack. In my case I am extracting some date data from an xml column. The following query throws "Arithmetic overflow error converting expression to data type datetime." if the piece of data found in the xml cannot be converted to datetime (in this specific case, the date is "0001-01-01" in some cases). Is there a way to detect this exception before it occurs? select [CustomerInfo].value('(//*:InceptionDate/text())[1]', 'datetime') FROM Customers An example of what I am trying to achieve in pseudocode with an imagined tsql function TRYCAST(expr, totype, defaultvalue): select TRYCAST( [CustomerInfo].value('(//*:InceptionDate/text())[1]', 'nvarchar(100)'), datetime, null) FROM Customers

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  • Properly populating tables in an Object Relational database

    - by chaosTechnician
    I've got a homework assignment that requires that I use Oracle 10g Express to implement an Object Relational database to track phone billing data. I have a superclass of Communications with subclasses of Call, Text, and Data. I'm hitting a snag with properly populating these tables so that I can find the appropriate data in the various tables. My Types and Tables are declared as such: create type CommunicationType as object ( -- column names here ) not final; create type CallType under CommunicationType ( -- column names here ); create type TextType under CommunicationType ( -- column names here ); create type DataType under CommunicationType ( -- column names here ); create table Communications of CommunicationType ( -- Primary and Foreign key constraints here ); create table Calls of CallType; create table Texts of TextType; create table Datas of DataType; When I try to insert data into one of the subclasses, its entry doesn't appear in the superclass. Likewise if I insert into the superclass, it doesn't show up in the appropriate subclass. For example, insert into Calls values (CallType( -- Values -- )); doesn't show any data in Communications. Nor does insert into Communications values (CallType( -- Values -- )); show anything in Calls. What am I doing wrong?

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  • linq join query

    - by SamB09
    Hi, im trying to do a join in linq , however for some reason i cant access the primary key of a table. It's the 'h.ProjectId' that doesn't seem to be accepted. The following error is given CW1.SearchWebService.Bid does not contain a definition for 'ProjectId' and no extention method 'ProjectId' accepting a first argument of type 'CW1SearchWebService.Bid' var allProjects = ctxt.Project.ToList() ; var allBids = ctxt.Bid.ToArray();// return all bids var projects = (from project in allProjects join h in allBids on project.ProjectId equals h.ProjectId

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  • Linq is returning too many results when joined

    - by KallDrexx
    In my schema I have two database tables. relationships and relationship_memberships. I am attempting to retrieve all the entries from the relationship table that have a specific member in it, thus having to join it with the relationship_memberships table. I have the following method in my business object: public IList<DBMappings.relationships> GetRelationshipsByObjectId(int objId) { var results = from r in _context.Repository<DBMappings.relationships>() join m in _context.Repository<DBMappings.relationship_memberships>() on r.rel_id equals m.rel_id where m.obj_id == objId select r; return results.ToList<DBMappings.relationships>(); } _Context is my generic repository using code based on the code outlined here. The problem is I have 3 records in the relationships table, and 3 records in the memberships table, each membership tied to a different relationship. 2 membership records have an obj_id value of 2 and the other is 3. I am trying to retrieve a list of all relationships related to object #2. When this linq runs, _context.Repository<DBMappings.relationships>() returns the correct 3 records and _context.Repository<DBMappings.relationship_memberships>() returns 3 records. However, when the results.ToList() executes, the resulting list has 2 issues: 1) The resulting list contains 6 records, all of type DBMappings.relationships(). Upon further inspection there are 2 for each real relationship record, both are an exact copy of each other. 2) All relationships are returned, even if m.obj_id == 3, even though objId variable is correctly passed in as 2. Can anyone see what's going on because I've spent 2 days looking at this code and I am unable to understand what is wrong. I have joins in other linq queries that seem to be working great, and my unit tests show that they are still working, so I must be doing something wrong with this. It seems like I need an extra pair of eyes on this one :)

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  • Sybase stored procedure - how do I create an index on a #table?

    - by DVK
    I have a stored procedure which creates and works with a temporary #table Some of the queries would be tremendously optimized if that temporary #table would have an index created on it. However, creating an index within the stored procedure fails: create procedure test1 as SELECT f1, f2, f3 INTO #table1 FROM main_table WHERE 1 = 2 -- insert rows into #table1 create index my_idx on #table1 (f1) SELECT f1, f2, f3 FROM #table1 (index my_idx) WHERE f1 = 11 -- "QUERY X" When I call the above, the query plan for "QUERY X" shows a table scan. If I simply run the code above outside the stored procedure, the messages show the following warning: Index 'my_idx' specified as optimizer hint in the FROM clause of table '#table1' does not exist. Optimizer will choose another index instead. This can be resolved when running ad-hoc (outside the stored procedure) by splitting the code above in two batches by addding "go" after index creation: create index my_idx on #table1 (f1) go Now, "QUERY X" query plan shows the use of index "my_idx". QUESTION: How do I mimique running the "create index" in a separate batch when it's inside the stored procedure? I can't insert a "go" there like I do with the ad-hoc copy above. P.S. If it matters, this is on Sybase 12.

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  • transforming from 'Y' or 'N' to bit

    - by rap-uvic
    Hello, I have a table which has a column called Direct of type char(1). It's values are either 'Y' or 'N' or NULL. I am creating a view and I want the value to be transformed to either 0 or 1 of type bit. Right now it's of type INT. How do I go about doing this? Following is the code: CASE WHEN Direct = 'Y' THEN (SELECT 1) WHEN Direct <> 'Y' THEN (SELECT 0) END AS DirectDebit

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  • Deeply nested subqueries for traversing trees in MySQL

    - by nickf
    I have a table in my database where I store a tree structure using the hybrid Nested Set (MPTT) model (the one which has lft and rght values) and the Adjacency List model (storing parent_id on each node). my_table (id, parent_id, lft, rght, alias) This question doesn't relate to any of the MPTT aspects of the tree but I thought I'd leave it in in case anyone had a good idea about how to leverage that. I want to convert a path of aliases to a specific node. For example: "users.admins.nickf" would find the node with alias "nickf" which is a child of one with alias "admins" which is a child of "users" which is at the root. There is a unique index on (parent_id, alias). I started out by writing the function so it would split the path to its parts, then query the database one by one: SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users';-- 1 SELECT `id` FROM `my_table` WHERE `parent_id` = 1 AND `alias` = 'admins'; -- 8 SELECT `id` FROM `my_table` WHERE `parent_id` = 8 AND `alias` = 'nickf'; -- 37 But then I realised I could do it with a single query, using a variable amount of nesting: SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` = ( SELECT `id` FROM `my_table` WHERE `parent_id` IS NULL AND `alias` = 'users' ) AND `alias` = 'admins' ) AND `alias` = 'nickf'; Since the number of sub-queries is dependent on the number of steps in the path, am I going to run into issues with having too many subqueries? (If there even is such a thing) Are there any better/smarter ways to perform this query?

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  • MSDN about stored procedure default return value

    - by Ilya
    Hello, Could anyone point exactly where MSDN says thet every user stored procedure returns 0 by default if no error happens? In other words, could I be sure that example code given below when being a stored procedure IF someStatement BEGIN RETURN 1 END should always return zero if someStatement is false and no error occurs? I know that it actually works this way, but I failed to find any explicit statement about this from Microsoft.

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  • Is closing/disposing an SqlDataReader needed if you are already closing the sqlconnection?

    - by Brian
    I noticed This question, but my question is a bit more specific. Is there any advantage to using using (SqlConnection conn = new SqlConnection(conStr)) { using (SqlCommand command = new SqlCommand()) { // dostuff } } instead of using (SqlConnection conn = new SqlConnection(conStr)) { SqlCommand command = new SqlCommand(); // dostuff } Obviously it does matter run more than one command with the same connection, since closing an SqlDataReader is more efficient than closing and reopening a connection (calling conn.Close();conn.Open(); will also free up the connection). I see many people insist that failure to close the DataReader means leaving open connection resources around, but doesn't that only apply if you don't close the connection?

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  • Oracle PL/SQL Import Japanese values CSV file

    - by cedric
    Hi. I am having problem with importing csv files containing values in japanese characters. When I do so it will display garbage when I query. my OS is japanese. My encoding for oracle NLS_LANG is JAPANESE_JAPAN.JA16SJISTILDE. I don't know what the problem is. When I try to import the very same file in some of my office mates' PC it just works fine

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  • sqlite3 date and interval functions

    - by umuthorax
    Hi, I wonder whether sqlite3 supports interval function. The following statement is accepted by PostgreSQL, however sqlite3 failed to parse it; select ... from orders where ... and o_orderdate < date '1995-03-01' + interval '3' month Error: near line 4: near "'1995-03-01'": syntax error Then, I modified the statement a little bit such as; and o_orderdate < date('1995-03-01') + interval '3' month This time the error was; Error: near line 4: near "'3'": syntax error Unfortunately, same trick did not work for the interval function i.e. and o_orderdate < date('1995-03-01') + interval('3' month) or and o_orderdate < date('1995-03-01') + interval('3') month or even and o_orderdate < date('1995-03-01') + interval(3 month) still gave me the syntax error. Maybe sqlite3 does not support interval function or am I missing something in its usage? Thanks a lot

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