A schema of a database system is its structure described in a formal language supported by the database management system (DBMS) and refers to the organization of data to create a blueprint of how a database will be constructed (divided into database tables).

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How To Hide Schema from user

I have DB with 2 schemas: A and B. B schema's procedures use A schema's procedures. I need to create user, which will not be able to see A schema. This user can use only B schema, but i want to let ...
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83 views

Cloning Postgres schema/tables across multiple servers

I'm working on a project that has databases across multiple servers, with one server for each business client. The project has some identical 'base' tables that are present in all the databases (for ...
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1answer
629 views

How to transfer the ownership of the dbo schema in SQL Server 2012

I've accidentally given a user the ownership of the db_owner schema (using the check box in the UI as below) and now I cannot: Transfer ownership to another user Drop the user from DB (though I can ...
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2answers
230 views

Oracle - Is it possible to maintain transaction across multiple schemas?

I got this database in oracle which includes 4 schemas. Each schema represents a logical layer. Each transaction (Stored Procedure) in the upper layer breaks into a couple of transactions in the lower ...
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1answer
155 views

Should I extract / normalize the mailing address despite requirements limiting number / type of addresses?

I currently am working on a contacts application (similar to Outlook contacts combined with eVites and LinkedIn). The requirements for the application are to limit the addresses (and phone / email ...
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1answer
136 views

Data Sync between servers with different schema in SQL Server [closed]

I have two servers 2008 R2 and 2005. The e-commerce site has been running with 2005 Server i has migrated 2005 server data with modified data schema to 2008 R2 from yesterday's date of data. My client ...
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3answers
381 views

Many to many link tables with history? [closed]

While creating a PostgreSQL database of customer subscribed services with DNS domains, I want to: enable customers to subscribe to multiple services each service can have multiple domain names per ...
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1answer
166 views

message table schema - body TEXT or varchar [closed]

I want to make a small social network. For messaging body which one is more suitable? VARCHAR or TEXT? if VARCHAR how long is efficient?
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95 views

How to reduce table duplication, while ensuring integrity of the database?

For example, in my app I have some class called Contact: case class Contact(name: String, email: String, phone: String) And several other classes have one-to-many relation to that contact (for ...
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2answers
185 views

How can I integrate a new system to a design scheme I previously created?

This is a follow-up to a question I wrote a while ago, for reference, you can look it up here. I've developed a curriculum based database scheme that looks like this(Thanks Joel Brown) Now that a ...
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2answers
574 views

Multi-Tenant (SaaS) Database Schema with Sharing

Guys I just need your opinion which is the best approach to design a schema of a database for a SaaS application. I want it all on a single database, At first I think I can simply put a context_id ...
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2answers
1k views

Import Oracle schema data without losing modifications of stored procedures

I have this scenario: One huge (thousands of tables), complex production database, Oracle 8 One huge (thousands of tables), complex development database, Oracle 9 ( same structure as production ) ...
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26 views

Create a schema like an existing schema [duplicate]

I have a existing schema in my database called SCOTT, how can I create a new schema with exactly the same privileges which SCOTT schema is having? Is there any create like or some command to create ...
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3answers
67 views

ER Schema “Optimisation”

I am trying to make an ER Schema for a person. The person will have Current Address and Permanent Address. So far I have it so that both Current and Permanent Address are Composite Attributes and they ...
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1answer
81 views

Constrains relationship

I have the following design. Each user has it's own contacts, it's own hosts and assign those to a domain which belongs only to him. I want to insure that the host you assign to the domain belongs ...
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2answers
426 views

Which schema is better for a shopping project? [closed]

I'm working on a business-to-customer project that has variety of product types. There are a few properties like name, description, brand_id that each product has but there are also many specialized ...
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2answers
748 views

DB2 (LUW) equivalent for Oracle “drop user cascade”

This question is related to creating and initialising test and development databases for an application that has the database running on LUW (linux-unix-windows) On oracle, we have an os user (on ...
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2answers
333 views

SQL Server 2008 R2 : A Possible indexing strategy for the given schema?

We have these four tables: Store ( row bigint, id uniqueidentifier, name varchar ) Products ( row bigint, id uniqueidentifier, storeID uniqueidentifier, productname ...
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109 views

Are duplicates ever acceptable in a database

A warehouse system I am working on allows inwards consignments [type = 0] and outwards consignments [type = 1]. The user selects multiple products for each consignment and then multiple warehouse ...
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1answer
855 views

Schema Change/Update script for Database deploy [closed]

I have a need to change the database schema . I'm planning to write Schema change and update scripts for tracking database changes and updating them. I followed Versioning Databases – Change Scripts ...
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1answer
121 views

Whether or not to create separate tables

I am working on a project, where I need to store the information related to A and B, the A and B both have identical columns.There might be thousands of As and Bs. Should I use "type" column to ...
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1answer
88 views

is there a recommended way to update many postgres schemes

I have a database in postgres which has 15 schemes, the schemes are identical with the same tables, views and functions. the system uses one scheme at a time, as if they were separate databases. So ...
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1answer
355 views

How does security context propagate between schemas within a database?

We have a SQL Server 2008 database that contains two schema's. The owners of these schema's have been granted full SELECT permissions to all tables within each others ownership. I have created a ...
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2answers
110 views

What is a standard or conventional name for a column representing display order? [closed]

For example, a junction table associating a product and its pictures: create table product_picture ( product_id bigint not null references product(id), picture_id bigint not null references ...
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1answer
58 views

How to handle “or” possibilities in MongoDB

I'm new to MongoDB and by no means an expert in DB design in general. This feels like a really basic question that's probably been answered a million times, but I'm having a surprisingly hard time ...
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4answers
132 views

Is there a DB that will allow the same field name with different cases?

Is there a DB that will allow a user to create a table with two fields, one calls MYFIELD, the other called myfield?
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293 views

Why can't the schema owner create a new table?

I have a DB user called STANMAN which owns the STANMAN schema. When I try to create a table as STANMAN, it says STANMAN has insufficient privileges. How could a schema-owner not already have ...
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Open source tools for Oracle schema compares

I'm looking for an open source tool to generate DDL scripts. Many tools call these synchronization scripts. We essentially want to compare schema of different environments (ie: DEV to QA, QA to ...
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1answer
161 views

MySQL Performance Gains By Splitting Tables?

I am designing a database schema to be used with MySQL. The database needs to keep track of a users basket items and purchased items. I've thought about two ways I could do this but not sure which ...
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691 views

which role-permission database design?

I want to manage roles and permissions. Most of designs on web look like this tables: Users Roles UserRoles Permissions RolePermissions Here, what is permissions? I am thinking for such a design ...
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1answer
800 views

What's a good way to model user authorization to hierarchical data?

I'm wanting to implement something that's basically an ACL in SQL Server (2008, we'll be moving to 2012). We're working with farm production information. We will have users who need to be authorized ...
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1answer
478 views

Creating schema for a shop that sells items from multiple tables

I am trying to create a table in mySQl that contains a list of all the items that a shops. For example: shops (shop_ID (PK), shop_name) shops_and_items (shop_ID (PK), item_ID (PK), price) The issue ...
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3answers
248 views

Database design for conditional detail table

I have an expense management system for monthly expenses. Expenses are of two types: one-time monthly expenses, and daily expenses for each day of month. I have created the following tables: ...
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1answer
638 views

Oracle schema migration to new database with zero downtime

I have a problem: I have two production schemas on one database each serving two different appplicaitons. I need to migrate (move) one schema to an entirely new database that will be dedicated for ...
2
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1answer
113 views

Column type unknown at creation time

I have a table in a MySQL database that stores survey results. CREATE TABLE survey_responses ( response_id INTEGER UNSIGNED AUTO_INCREMENT, survey_id INTEGER UNSIGNED NOT NULL, question_id ...
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1answer
7k views

How can extract the table schema from just the .frm file?

I have extracted the data directory of mysql from a backup and need to get the schema from an old table, however it's a backup from a different machine. I have read a fair number of tutorials today ...
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1answer
55 views

Strategies for summary data in parent record based on detail data?

I have parent-child relationship as shown below. I need to find the first order date for each customer. Obviously, writing a query to do this is fairly straight-forward but it does require reading all ...
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4answers
586 views

How can a database be normalized when an optional field causes denormalization?

Suppose you have a warehouse full of widgets. Each widget in the warehouse is stored in a specific identifiable location within the warehouse. You might have a schema which looks like this: A ...
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1answer
1k views

Candidate key = Key = Minimal Superkey?

I got a little confused by all these keys. As I understand A key of a relational schema = The minimal subset of a superkey that is still a key = A candidate key Is this correct or not?
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1answer
97 views

When is it worth it to use Triggers and stored procedures/functions? [closed]

As an example, lets say I have a forum application and for every topic that is created, I have a trigger that fires a database function creating a post.(lets assume we have a topics table and a post ...
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1answer
140 views

Mysql: Schema/Query Performance Approach for aggregated mailbox folders

I am about to code a messaging system where users can write messages to other users. User can create custom inbox folders for sorting the messages they receive, however, every user has 2 main inboxes: ...
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1answer
188 views

What is the meaning of this anomaly warning message?

I have run an analysis with SchemaSpy. The tool gave me a warning message for two tables. The warning message is: Tables with incrementing column names, potentially indicating denormalization ...
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1answer
124 views

Many:Many with Shared Relation

I'm modelling data with multiplicity like this: Each Composition/Anthology related pair must share a Composer. Also, each Anthology must contain at least one Composition. How would you recommend I ...
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1answer
213 views

Postgres - Schema information within Trigger?

Background : (Multi-tenant design;separate schema per customer, all table structures identical;Data-warehouse / non-OLTP system here; Postgres 9.2.x). Reviewing patterns for the following problem: I ...
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1answer
2k views

Oracle database created whats next? Create Schema or Create Tablespace?

I'm a programmer that's being thrown to the DBA/Sysadmin island all by myself with a volleyball that I named Wilson. I'm trying to survive here. I'm supposed to create a database for an application. ...
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298 views

XML Data convert to SQL database,

I have an XML feed that i need to parse daily, i want to store all of the data from the XML feed in a SQL table so then that data can be queried and manipulated by my clients. I can currently parse ...
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2answers
230 views

PostgreSQL and default Schemas

Whenever I create a brand new database in PostgreSQL Maestro it creates the following list of default schemas: Now from my understanding Schemas are like folders for organization, etc. So the ...
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82 views

In regards to GS1 barcode - what size DB field are used?

In regards to GS1 barcode - what size DB field is used or is the entire GS1 typically not stored in database, but rather processed in the application layer and stored in the database as a collection ...
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290 views

Database schema design help needed

I am developing a PHP application expecting millions of records both parent and children. My goal is to design an optimized database design to achieve high speed and performance. This application ...
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How do I list all schemas in PostgreSQL?

When using PostgreSQL v9.1, how do I list all of the schemas using SQL? I was expecting something along the lines of: SELECT something FROM pg_blah;