database-schema

问题 To prevent the usage of the schema attribute in the table annotation to all of my entities, I set the default schema name by the schema.xml: <?xml version="1.0" encoding="UTF-8"?> <entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm orm_2_0.xsd" version="2.0"> <persistence-unit-metadata> <persistence-unit-defaults> <schema>X</schema> </persistence-unit-defaults>

问题 The database-schema (Source and target) are very large (each has over 350 tables). I have got the task to somehow merge these two tables into one. The data itself (whats in the tables) has to be migrated. I have to be careful that there are no double entries for primary keys before or while merging the schemata. Has anybody ever done that already and would be able to provide me his solution or could anyone help me get a approach to the task? My approaches all failed and my advisor just tells

问题 I'm trying to figure out how to implement migration between two databases. My plan is Create mysqldump --no-data of source DB Create mysqldump --no-data of target DB Create alterscript based on 2 created mysqldump files Run alter script on target DB to migrate new changes However I haven't found a way to compare 2 mysqldumps and create alter script from that. Is there any tools for that? -kari 回答1: Looks like this tool does what I need. http://search.cpan.org/dist/MySQL-Diff/bin/mysqldiff I

问题 I'm trying to create a database to manage autobus data CREATE TABLE Company( Company_Name VARCHAR(12), Tel INT, PRIMARY KEY(Company_Name) ); CREATE TABLE Line( ID_Line VARCHAR(3), NCompany_Name VARCHAR(12), Desc TEXT, PRIMARY KEY(ID_Line, Company_Name), FOREIGN KEY (Company_Name) REFERENCES Company(Company_Name) ); CREATE TABLE Stop( ID_Stop VARCHAR(3), geoLat FLOAT(10,6), geoLong FLOAT(10,6), PRIMARY KEY(ID_Stop) ); CREATE TABLE Make( ID_Stop VARCHAR(3), ID_Line VARCHAR(3), Hour TIME,

问题 I am developing a system that will have a database backend. I am intending that every table have a PK that is arbitary, system generated and maintained. My environment (for development and production) is Windows 7; Delphi; and an embedded database (probably Firebird). My data structures include one table OWNER, that has very little information associated with it - probably no more than name and description. The rest of the data structure will be about 50 tables, each with name and description

问题 I am trying to create a database schema for the following model: I am not sure what the better way to represent this in a MongoDb would be, but since I am using Mongoose and there is a plugin for inheritance, I am trying the following: var mongoose = require('mongoose') , extend = require('mongoose-schema-extend') , Schema = mongoose.Schema , ObjectId = mongoose.Schema.Types.ObjectId var db = mongoose.connection; db.on('error', console.error.bind(console, 'connection error:')); db.once('open'

问题 I've been working on a small but somewhat complex Rails application with multiple has_and_belongs_to_many relationships. It's open source, and the code is here. Everything was working fine, but recently I added a new HABTM relationship migration, and an rspec test started to fail. Rake:db:migrate was working (and the issue was working locally), just not in testing. Upon running db:test:load --trace , I get the following error: :fermi og$ rake db:test:load --trace /Users/og/.rvm/rubies/ruby-1

问题 I'm looking for a way to query flatfiles with custom file-extensions directly via SQL. Normally use something like SELECT * FROM [Text;DATABASE=C:\Flatfiles].[S7121070_ppis#csv] which works terrific with .txt, .csv and .tab. However, in my current project I work with fixed-width flatfiles with an .ftp7-extension. When querying those files in with VBA, I encounter Err# -2147217911, stating that the object or database is locked. Oddly, this occurs only whenever I querying anything that's not a

问题 I have been trying to work this one out. In cakePHP 2 I could use: $tables = ConnectionManager::getDataSource('default')->listSources(); But in CakePHP 3.x I can't work out what to use? I have looked at the link cakephp get schema for list of tables Unfortunately it doesnt help with cakePHP 3.0? 回答1: We can get list of table in cakephp3 using very similar pattern as $tables = ConnectionManager::get('default')->schemaCollection()->listTables(); 回答2: I just had the same problem. Try using the

问题 I have some code of ADO.NET to dynamically detect the database schema, what I need is how to get unique columns constraints and Primary key constraints using the GetSchema method on SqlConnection . This is the code that I have: conn.Open(); SqlCommand mSqlCommand = new SqlCommand("sp_pkeys", conn); mSqlCommand.CommandType = CommandType.StoredProcedure; mSqlCommand.Parameters.Add( "@table_name", SqlDbType.NVarChar).Value = tableName; SqlDataReader mReader = mSqlCommand.ExecuteReader(