Sql Definition and 77 Threads

Non-DBA advanced part: For me subqueries, HAVING clause, GROUP BY clause, CTEs, Indexing, Optimization etc are advanced sql queries. This is mostly used for data analyst, data scientist etc type I mean. For DBA part: No idea What is advanced sql and how'd you learn it. For data analyst...

I am customer support engineer intern. My supervisor has assignmed me to learn SQL in 2 days. I've studied mysql in the past as well. https://www.w3schools.com/sql/ He has asked me to learn till SQL data types. Are there any video courses to revise my sql using mysql? Remember that this is for...

I expect output as 30,20,3,2,1 in a row but I am getting repetitions of these with 20,30 coming 3 times and 3,2 coming 18 times and 1 coming 16 times. I dont understand how combination of condition in where is leading to so many duplicates. Instead of using or if I divide the query into 2 and...

I have a T-SQL query (MS SQL Server) that runs slowly due to the six inner joins I need to get the data I want. The seven tables of data I am working with consist of four of category data and three of quantitative - and the query, which is not important to the question, just makes calculations...

Hey! :giggle: The following relations of a project administration of a company are given, where the primary key of the respective relations are underlined. An employee can be assigned to several projects. Furthermore, an employee can have different competencies, which are billed at different...

Hey! :giggle: Use the RADL database as a basis for formulating the following SQL commands. 1. Give an SQL expression that outputs all personnel information for the employee Ernst Pach. 2. Give an SQL expression that outputs all personnel information about the employees, who earn more than...

This is actually for my new Android app. But everything is written in Java and SQL; there is almost nothing that is specific to Android. I have a database, and the following three tables are of interest here: itemEntity with columns: itemID: integer primary key itemName: String; indexed to be...

Hi all, Curious if anyone has worked with SQL Server Dev 2017 with ML and Python Server, i.e., with the full data analysis platform and what your experiences are.

Hi All, Trying to do some querying in my (local) SQL Server. Thing is I am having trouble accessing my default instance, though no trouble accessing the one named instance I have. I have been to Stack Overflow , read up, posted a few things, then told to read again after it all failed. I get a...

Hi All, It seems SQL Server's Dev 2017 config manager does not come " built in" within , and it is now a snap in. When I try to install it through Control Panel, I get the error message: Cannot connect to WMI provider. You do not have permission or the server is unreachable...

Hi, Just curious: I was told, without proof, that declarative ( i.e., not purely imperative) versions of SQL are not strictly necessary, i.e., that anything that can be done within declarative extensions can also be done within the imperative "restriction" . So, e.g., anything in SQL Server that...

Hello, I'm looking for a book on relational databases, that uses SQL, that is practical with lots of examples, and the least possible amount of jargon. Specifically, I have issues understanding how to translate the E/R model into the relational model (relations to tables), and the book that I...

Hi All, I am kind of new to this, please be patient. I appreciate your input I have a SQL Server DB, I am trying to create a remote front end to give graphical, or at least simple access to the DB (Client-Server, of course). I would appreciate some suggestions. This is my way of breaking...

[I cannot find my SQL Server Configuration Manager] Hi, I have installed both SQL Server Express 2017 and SQL Server Developer 2017 (Separately; not one as a Default or Otherwise Instance) , and they have both run without any major problem. Issue now is that I want to allow a remote connection...

Hi All, Somehow the copy of AdventureWorks2014 I downloaded ( saved and restored) is missing the data, i.e., it contains the schema : tables, indexes, etc. , but many tables are missing the actual data. I have not done any delete/truncate/drop operations, so this may have been a problem with my...

Hi, given Sql server executes queries order from, where, group by, having, select, order by. Why don't we write queries in same order? Would that improve speed of execution ?

Hi, I want to practice queries that require having repeated records. This is not allowed by default since it violates uniqueness constraint. Do I just use an alter table drop unique constraint for this?

Hi All, I had to reinstall my SQL Server and I a having trouble finding the database engine which is the local host. Please see screenshots. Any ideas? Thanks.

Hi All, Sorry if this seems pretty lost. I want to compute an expression of the type A/B with data given in different sheets, i.e., A is given in sheet i and b is given in sheet j. Now, I know that in SQL Server ( SQL in general), one can join tables. Is there a similar way of getting data...

Hi All, I am trying to move databases ( together with associated data objects) between an instance in SQL Server Express (2016) and an instance living in SQL Server Developer 2017. I know that, between instances of the same version I can : 1) Copy the script in one instance and run it in the...

Hope this is acceptable and the right place to post: SQL Server Developer now free: https://www.microsoft.com/en-us/sql-server/sql-server-downloads Just thought some may be interested.

Hi All, I need to do a presentation in the subject areas of SQL Server, general Database into the area of Data Mining for a job interview. Any Ideas? First thought is the use of SSAS ( Analysis Service) and SSDT ( Data Tools) from SQL Server in Data Mining. But this does not seem...

Hi All, When a query is made in SQL , it is transcribed into FOL in the back end , and, if the transcription is a wff , the models, if any, are returned as the answer to the query. I have an idea of how the transcription works for basic statements, but, does anyone know the actual "...

Hi All, Say I have a SQL Server ( or more general, if possible) back end, i.e., stored at the server level. Now, I want to create a front-end, say Access fron- end ( again, if possible, more general ). I know one thing I need : to create a physical connection between the two, most likely...

Hi, I am trying to find all the even numbers in [FieldName] in SQL Server. My query is : SELECT [FieldName] FROM Table WHERE [FieldName] % 2 =0 ; I only get an error message . ( I am using SQL Zoo, since I don't have SQL server available at the moment. Only message I get is that the query is...

I use SQL Server at my job and for my personal projects (only because I'm familiar with it). Nevertheless I am always amazed at how the language doesn't provide any simple ways of solving common problems. For example, let's say I have some data which represents rows I want to insert or update...

I created a database on my website, and now I'm guessing I have to add tables for the information. I have no idea what I'm looking at when I'm asked to create a table.

Hi, I am storing a blob in my database running wamp64/MySQL and I am using AJAX to retrieve it. The code works with Chrome, Edge, and FireFox but I obtain the error message "Invalid State Error" in the debugger for the line "xmlhttp.responseType='arraybuffer'" when I run it under IE11. I...

I have a gut feeling that I will retake a test about these subjects. Do you know good resources about creating ER diagram and relational model for database (sql database primarily) Sometimes even creating a correct ER Diagram (chen notation) feels difficult and confusing. These type of...

SELECT c.object_id AS id, convert(smallint, c.column_id) AS number, s.colid, s.status, convert(varbinary(8000), s.text) AS ctext, convert(smallint, 2 + 4 * (s.status & 1)) AS texttype, convert(smallint, 0) AS language, s.text FROM...

Hi all, I successfully created (scripted) a database in MS SQL Server 2012. My problem is that while the database itself is listed in the object explorer , the tables from the database are not. The database I scripted did not contain actual data, i.e., there were no 'Insert' statements. Is this...

Hi i have an interest in gravity, space, and general developments. Background in in Telecoms and IT to management level. I Operate out of own business providing information solutions of various kinds from data collection, processing to visualisation. I always had an interest in electronics as a...

Hi, Just curious: is it possible/feasible to use SQL stored procedures as a front end? I mean, couldn't we design stored procedures to allow for easier querying if we knew the general type of queries that would be used for the application (of course, the application for which we designed the...

Hi all, I think I found the answer to determine whether two SQL tables are equal. Symmetric difference of sets: A(Symmetric Difference) B = ## A \cup B - (A\cap B) ##. One can show that sets A,B are equal iff A (Symmetric Difference) B =A (=B, of course) How does one implement this in the...

Hi all, I have a bunch of legacy files I am trying to import directly into an .sql database. Is there a way of doing this other than by using Microsoft's import/export Wizard?

Hi All, When operating on tables T1, T2 and obtaining a table T3, one obtains rows {##r_{3k}##} in T3 that are obtained from rows {## r_{1i}##} and {##r_{2j} ##} by what I call "concatenation" . I wonder if there is a formal name for it. Specifically, say, during an inner join between T1...

Hi All, Just curious as to what those with experience in creating databases believe is the best method when renaming databases: using Apex SQL , which (supposedly) automatically checks for dependencies or just sitting down , looking at the dependencies and doing the changes one by one as needed...

I have a 6GB .bak file that, when check it in the file to use for restore, the file shows 'Incomplete'. I need to extract the .mdf part of the .bak file since I don't need the .log file. There should be some way to do this or some tool out there that will either repair the .bak file so it...

Hi All, I am doing a query in which I am ALIASING a column name, say 'column name' AS x Can I , at the end of the query ORDER BY x, or must I ORDER BY the given initial 'column name'? (Still having trouble downloading free copy of MSSQL2012, so I cannot test the query). I know this has to see...

Could use some help figuring out the error Operand type clash: numeric is incompatible with uniqueidentifier which points to the specified line below CREATE PROCEDURE AddPartner @name NVARCHAR(50), @email NVARCHAR(254), @new_guid UNIQUEIDENTIFIER OUTPUT AS BEGIN SET NOCOUNT ON...

Hi all, just curious. I am just learning about user-defined functions in MSSQL2014. What kind of Math can we do with it? Didn't get much useful from my search.

Hi all, I am reviewing some material and I have been stuck on these (I am a slow starter, I guess) 1) I have the table Customer, which has an entry on sales reps for customers. I want to know which sales rep handles the most customers. Here is what is given Customer ( CustNum PK, CustName...

In my opinion, using Venn diagrams, or set theory in general, to help aspiring SQL programmers (yes, SQL is a programming language) understand joins causes nothing but confusion for literal-, logical-thinking persons like myself. Allow me to explain my opinion. Venn diagrams have always been...

Hi all :I have the table Emp (EmpNum PK, EmpLastNM, EmpEducation, EmpDependent, EmpEducation,...EMpHireDate) which I want to normalize and then I want to do an ERD for it. I must break this into tables one for which , it seems, I cannot have a non-null PK: Now EmpDependent is both...

Hi All, Hope this is not too simple/dumb. I think I have a good idea of what an inner join of two SQL tables T1, T2 along a common field F is, but , for an exercise, I am looking for a precise definition. I am looking for a definition of this sort: (please correct if necessary or let me know if...

I want to buy a book on SQL, but since I already have a basic level of professional SQL experience I want to make sure I'm getting a book that goes into depth on the underlying implentations of database transactions, the mathematical theory behind relational databases, how to optimize, etc. I'm...

Hi all, I am learning DDL ( as opposed to GUI ) table design in MSSL2014. EDIT I am given a table printout and I want as an output the(a) DDL code that would output the given table. Sorry, I don't have a scanner nor the original file in my PC, I have a table diagram in a piece of paper. I...

Hi all, Just curious as to whether it is a good rule of thumb ( though not an actual rule) that out of two effective queries (i.e., two queries q1, q2 that return the desired result) , the query that is shortest as a string, i.e., has the fewest total words, will run faster? I understand the...

Hi all, I have an .sql file; written as a set of commands, as a general text file, with a .sql extension. I need to execute it in order to get some tables as output, and then run some queries on these tables. Are there some free programs to run/execute the file? I got some hits on a search...

Hi all, I have some queries to do, which I want to save as an .sql file. What program can I /must I use to do this? I think I remember at some point using plain old Notepad to write the queries, since these are made of standard English commands, nothing too fancy. Would this work? Thanks.