A popular open-source embeddable (i.e. non client-server) RDBMS implemented as a C library.

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1answer
574 views

SQLite or CouchDB for Locational Data Mining Project?

I am currently designing a Data Mining Project where I am going to harvest rather large volumes of Twitter data in order to analyse locational data (geocoded tweets) and do some machine learning with ...
2
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1answer
2k views

Working with multiple databases?

Using sqlite3 on Linux, how can one work with multiple databases? I'd like to do something like the following in database 1? sqlite3 database1.db insert into database1.mytable values (select * from ...
2
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1answer
147 views

File database vs application server database for concurrent performance & bulk data

I asked a question about Ripple's database implementation, and received this response: The ripple server uses SQLite for structured data and a configurable "back end" for unstructured "bulk" ...
2
votes
1answer
75 views

Rewrite sqlite trigger to postgresql

Can you help me please with this problem? I need rewrite this simply trigger from sqlite to PostgreSQL format: In sqlite: CREATE TRIGGER connections_INSERT_update_connection_root_trg ...
2
votes
1answer
2k views

Default values in SQLite3

When I created the table structure of my SQLite database, I provided a DEFAULT value which is used when no value is provided by the user. Now, because the application code changed, I need to modify ...
2
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1answer
1k views

How to create a train schedule in SQLite3?

I am interested in what a SQLite3 database schema would look like for a train timetable. Generally this is presented in table format as the final result. Sample Schedule for M to F STATION A ...
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0answers
28 views

Spatialite: use of virtual spatial index for distances

I'm currently learning to use spatial access methods for query optimization. I'm going through the examples in spatialite cookbook and got stuck in here ...
2
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0answers
43 views

Improving performance of a weighted search query in SQLite3

For an intra-site search I have this table in an SQLite3 database, that relates ids to search terms with a certain weight: CREATE TABLE search_index ( id INTEGER(7) REFERENCES other_table, ...
2
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2answers
106 views

Create a result for a line chart with dates

I have this table in SQLite which I use to record the risk level identified in vulnerability assesments according to the day the scan was performed. This table looks like this: Scan Date | Risk ...
2
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0answers
258 views

In-memory database vs RAM-disk

In SQLite, are there any differences in performance/features/reliability/... between: 1) an in-memory database: rc = sqlite3_open("file::memory:", &db); 2) a database on a RAM-disk? The ...
2
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1answer
320 views

Configuration options for relational algebra evaluator “ra.jar”

I am participating in the Stanford Database Class, and there are some problem sets to be solved in "mathy" relational algebra syntax. The course instructors demand from students to use this ...
2
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1answer
1k views

Enable autocomplete in an sqlite3 interactive shell

I am using sqlite3 on a machine where I can use tab completion (ie .read abc<tab> will autocomplete to .read abcdefghij.db. I would like to know how to enable this on my personal machine. Edit ...
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0answers
554 views

SQLite Performance Tuning

I have the following query, which fetches data from only one table. It is a query which is supposed to return data for an autocomplete function. Autocomplete data can be in text1 or text2. The ...
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2answers
1k views

Improving `GROUP BY` query performance in sqlite3

I have a little web-application that is using sqlite3 as it's DB (the db is fairly small). Right now, I am generating some content to display using the following query: SELECT dbId, dlState, ...
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4answers
2k views

RAM/memory based databases

I am looking for a RAM/memory based database, and these two seem to be interesting: SQLite Oracle Berkeley DB Do you have any other suggestions? I need more than one executable to be able to ...
1
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2answers
83 views

How to select data in the same table on different rows that are empty?

I use this select on my SQLite database: SELECT attributeX FROM table GROUP BY attributeX HAVING COUNT(attributeY) = 0; My table: attributeX (type integer) | attributeY (type text) ...
1
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1answer
99 views

sqlite database: advanced SQL or redesign

I've been programming for several years, but I'm pretty new to SQL(ite). I'm designing a database for a sort of a bookkeeping program. What I've got so far: orders (o INTEGER PRIMARY KEY, ...
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vote
1answer
2k views

Why does SQlite return incorrect sum?

CREATE TABLE "Test" ("ItemQty" DOUBLE NOT NULL ); Insert Into Test VALUES (1.4); Insert Into Test VALUES (1.4); Insert Into Test VALUES (1.4); Insert Into Test VALUES (1.4); Insert Into Test VALUES ...
1
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1answer
30 views

Order By with duration strings having time units

I have a SQLite database with a table "Rate" who has a column "timeToMaturity". This column contains strings such as : 7Months 26Days 3Years I'd like to order a query results by timeToMaturity ...
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2answers
345 views

Create database with multiple columns using SQLite in Android Studio

I want to create a database with 3 columns (name of point of interest, longitude and latitude). Since I am completely new to databases I am using an example I found online and try to change it to my ...
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1answer
54 views

Will my sqlite database occupy less space if I insert nulls instead of zeros

I have a table where most of the values inserted in one of the columns are 0. Should the database be smaller if I insert nulls instead of zeros?
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2answers
108 views

New to databases - does my ERD reflect good database design?

I'm making a database to hold data for a media player that I'm working on. Originally, I thought to use one table with the fields: {filePath,artist,title,album,track_number,length,date,artworkUrl} ...
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1answer
1k views

Joins in Update statement in sqlite

CREATE TABLE Table_1 ( Id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL , EmailId VARCHAR ) INSERT INTO Table_1 VALUES (1,'raj@gmail.com'); INSERT INTO Table_1 VALUES (3,'test@gmail.com'); ...
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1answer
375 views

Cartesian product of two tables not working as expected in MySQL but fine with SQlitee?

I was practising some sql joins and decided to create a schema online rather than using my local database on sql fiddle. My schema is pretty simple table 1 (5 entries): (emp->{id,name,dep}) table ...
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1answer
70 views

Joining three tables

I have a question Find the titles of all movies not reviewed by Chris Jackson Where the relations are 3 movie(mID, title, year, director), reviewer(rID, name), rating(rID, mID, stars, ratingDate) ...
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1answer
28 views

How do I query for fields that have AT LEAST a given range?

Say I have a table of the form: +-----+-------+ | Key | Value | +-----+-------+ | A | 1 | | A | 3 | | A | 4 | | B | 2 | | B | 3 | | C | 3 | | C | 4 | | C | ...
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1answer
27 views

parent child records - cascade deletes or transactions?

I'm about to create a parent and child table. In planning how to do CRUD operations on this data, I was wondering what is better design when it comes to deleting data. I'm using SQLite. I know ...
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1answer
52 views

Query for hierarchical RBAC scenario

I have a SQLite database with a hierarchical role-based access control (RBAC) data model. In this model, users are granted permissions to perform certain actions against various resources either ...
1
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1answer
57 views

How to get a surrogate key value in order to put a foreign key in and create relationship?

I am trying to create two relationships between three tables, using foreign keys with values of primary keys, which are surrogate keys. But I don't understand how to enter the right value in the ...
1
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1answer
56 views

Child records under the parent record in SQLite [closed]

I have two tables for Billing, one Bill_Master and other is Bill_Detail. The records in both tables are as follows... **BILL_MASTER** id party bill_amount 1 abc 500 2 def ...
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vote
1answer
429 views

How to get the rowid in a TRIGGER for another table in SQLite

Given the below schema CREATE TABLE Item ( _id INTEGER NOT NULL, name NVARCHAR NOT NULL, parent INTEGER NULL CONSTRAINT fk_Recursive ...
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1answer
267 views

SQLite and Write Ahead Logging: why so large files

I have been doing some operations on SQLite databases recently. The other day I ran a command to DELETE a bunch of rows from a 1GB database file and the WAL file got over 8GBs at which point it ...
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2answers
3k views

join for between multiple tables without common fields

table E : id, title, datetime table L : id, place, xpos, ypos table M : id, title, datetime, contact, agenda table ER : parentid, childid, parenttype, child type data in ER : e.id, l.id, e, l -> E ...
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1answer
914 views

How do I query for leaf nodes in a hierarchy using a closure table?

I have some hierarchical data (representing musical instruments and playing techniques), where each leaf in the hierarchy is an audio file. The nesting depth of leaf nodes will vary because some ...
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1answer
347 views

Database schema for a variable-level hierarchy with variable types?

A client is asking for a database structure for a medical translation app that involves narrowing down a health issue and then asking specific questions on it. The tricky part of representing this in ...
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2answers
6k views

disk I/O error in SQLite

What are the possible things that would trigger the "disk I/O error"? I've been having this problem and I couldn't find a solution. I have a SQLite3 database, and I'm trying to insert data from a file ...
1
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1answer
185 views

Database design: nested tagging

I have a situation that after an initial thought ended in the following tables: section: id, name section_tag: id, name section_tag_map: section_id, tag_id item: id, name ...
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vote
1answer
456 views

Referencing multiple tables from a single table and store additional data

I have a database where I want to store lap time information from a racing game. I have tables for car, track, game, tuning and upgrade data and want to put all these together to create a single ...
1
vote
1answer
271 views

Delete word, its meanings, its meaning's example sentences from DB

I have three tables as below (simplified for demonstration): words ===== integer id text word meanings ======== integer id integer word_id text meaning examples ======== integer id integer ...
1
vote
1answer
392 views

How can I create a MySQL database based on a SQLite schema?

I have MySQL on my server and different SQLite databases on a client. I'm trying to find a way to create the same databases on the server. Since a SQLite schema is actually a CREATE query, one way ...
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1answer
116 views

Check ruby gem and SQLite3 for FTS3 or FTS4 support

I have installed SQLite3 on Mountain Lion via MacPorts and Ruby along with sqlite3 gem using RVM. I'd like to know if there's any way for me to understand if my SQLite3 installation supports FTS4. ...
1
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1answer
4k views

Combine column from multiple rows into one row in SQLITE

I have a sqlite-database with the schema Articles Id Name Tags Id Name ArticlesTags Id ArticleId TagId I´m trying to query for Articles.Name and a LIST of tags. Basically what I would want ...
1
vote
1answer
1k views

Looking for a tool to convert between MySql, Sql Server CE, Sql Server and SQLite [closed]

Our old product supports 4 different database types for storing data: SQLite MySql Sql Server CE Sql Server There is also an export feature, which allows to export some data and here is the ...
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0answers
21 views

Efficient way to load referenced data in one query [migrated]

My application uses a database to save its data. I have table Objects that looks like localID | title | content 1 Test "1,embed","3,embed","5,append" and another table ...
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0answers
83 views

Are there any known benchmarks/statistics on UnQLite?

I came across UnQLite the other day in Stack Overflow and it has me intrigued for some software I'm working on. However, very few tests have been published on how well it performs. There are plenty of ...
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0answers
50 views

SQLite insertion with junction table

I need to write a transaction for SQLite, that adds a blog post and links it to content tags, and it seems to be a bit too complicated for me. Here's an example schema: CREATE TABLE blogpost( ...
1
vote
1answer
20 views

Should I use VACUUM on a SQLite db with a log-structured filesystem?

I'm runnig a SQLite database on nilfs (which is a log-structured filesystem). Every now and then I delete old records, so that the size of the database never surpass a certain amount. But since the ...
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vote
1answer
224 views

SQLite disk I/O error (3850)

I can't seem to figure out what is causing the I/O Error: $sqlite3 db.sqlite < data.sql (3850) disk I/O error Error: near line 2: disk I/O error (3850) disk I/O error Error: near line 3: disk ...
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vote
1answer
21 views

How to optimize search restricted by boolean column?

I want to optimize a query1 of the form SELECT yid, xid FROM x WHERE is_principal; Here, is_principal is a non-null boolean column of x. If I run EXPLAIN QUERY PLAN on this query, the output I get ...
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0answers
177 views

Migrate from SQLite to MySQL (then back)

For various reasons, I must use a SQLite database with a local application. However, I wrote a Flask app that enables users to more easily classify items in the database, and it runs very slow on ...