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

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2k 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 ...
2
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2answers
139 views

EAV-like table with both primary column pointing to the same foreign column

Background: I'm a programmer who, while had to work with simple databases several times, never had to work with complex ones. I.e. I'm proficient with basic stuff, but clueless about advanced features ...
2
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2answers
155 views

Query to find Maximum friends not giving correct resuts [closed]

Table Schema for the Likes table: id id1 1 2 1 3 2 1 I count the total number of Likes for each student with this: select id,count(*) from friends group by id I have to find the students with ...
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2answers
69 views

Create Sqlite3 database

I am simply trying to create a database. In my account's home directory, I type in sqlite3 test.db Then once I am in sqlite, I type .quit That should create the database file in the ...
2
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2answers
824 views

Reordering data in a table

I have a table that stores sensor data (in SQLite) and looks like this; TABLE Timestream: idTimestream PK autoincrementing integer, time int not null, value float not null, idSensor integer not ...
2
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1answer
3k views

Is there any way to get the position of a value in a table returned by a SELECT statement?

I have the following statement: SELECT id FROM myTable WHERE aCondition == 1 ORDER BY id which returns a table like this one for example: id 1 3 4 5 But what I need is to know the position of a ...
2
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4answers
177 views

Is there a “standard way” to log network messages (events) into a database?

I have two applications communicating over a LAN via events contained in network messages. Each message (i.e. an UDP packet) contains only one event. Messages are heterogeneous, meaning that the first ...
2
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1answer
69 views

Finding interval overlap between two tables

I have two tables that have top_depth, bottom_depth, lith_type. One defines the different layers found in a borehole and the other define where samples are extracted in each of the layers. I would ...
2
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2answers
73 views

Strategy to find the unique bivariate polynomials

I have table that stores Tutte polynomials of a large set of graphs. These are bivariate polynomials with integer coefficients. An example of a polynomial taken from Wikipedia is: Since the ...
2
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1answer
959 views

Why is SQLite adding unused disk space to “free-list” after deleting a lot of data in a database?

The SQLite FAQ states the following: (12) I deleted a lot of data but the database file did not get any smaller. Is this a bug? No. When you delete information from an SQLite database, the ...
2
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1answer
1k views

Track daily view count of youtube videos

I am making program that searches youtube for given keyword and need to get links of active videos. Term "active" means that video must have 1000 views per day. Youtube API doesn't give such ...
2
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1answer
736 views

Auto Increment Index Field For Create and Update

I'm trying to create an unique auto increment index field that is re-generated on both inserts and updates. I need it so that a client can send a server an integer and get back all outdated (created ...
2
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2answers
31 views

Finding opening and closing price using sqlite GROUP BY statement (accessing main query alias in subquery)

I want to preface this post by saying that I am a SQL(ite) newbie. My main goal is to find the opening/closing/high/low/average prices of each 5 minute interval of these stock prices. I can get the ...
2
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1answer
736 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 ...
2
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1answer
228 views

How to enforce an “exactly-one-per-group” constraint?

I have a table x that I've defined like this: CREATE TABLE x ( xid INTEGER NOT NULL PRIMARY KEY, yid INTEGER NOT NULL REFERENCES y(yid), is_principal BOOLEAN NOT NULL ); This definition ...
2
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1answer
138 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
87 views

What does 'Vacuum' do in Menial's Base 2 application?

I've had a look at the help documentation for Base 2, as well as Menial's product page, but haven't found an answer there. I've even clicked on the vacuum button and not noticed any change. What does ...
2
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2answers
68 views

Update function to enter random/unique GUID per row

I am new to SQL and am trying to do the following. i am using SQLite browser to edit the current file I have I do have a SQLite database with around 1500 rows of data that I would like to create a ...
2
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1answer
1k views

Is it possible to store and query JSON in SQLite?

I need to store JSON objects in a SQLite database, and then do complex queries on it. I did a table like this: +--------------------------------------+ |document | property | string | number| ...
2
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1answer
33 views

sqlite3 foreign keys ignored

I am working on a small sqlite3 database for a small simple mailserver. I have created a new sqlite3 database and add executed this to pürepare it for data: BEGIN TRANSACTION; CREATE TABLE ...
2
votes
1answer
259 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
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2answers
11k 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 ...
2
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1answer
633 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 ...
2
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1answer
3k 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 ...
2
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1answer
74 views

SQLite WITH + UNION issue

my UNION queries cannot work when tables created by WITH are used, is this a SQLite limitation? for example - This works: with T_one as ( select * from T ), T_two as ( select * from T ) ...
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0answers
23 views

SQLITE Foreign key has to be re-added? [closed]

Currently I have a mysql database on my computer which I convert to sqlite database. On the sqlite database, I have transaction_detail table with a foreign key to transaction_master table. The ...
2
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0answers
75 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
90 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
171 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
478 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
votes
1answer
2k 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
661 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
2k 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
vote
1answer
79 views

Postgresql equivalent to sqlite pragma

What would be the equivalent of the sqlite pragma below if I want to get the best performance out of postgresql. pragma synchronous = OFF; pragma journal_mode = OFF; pragma count_changes = OFF; ...
1
vote
2answers
351 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) ...
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vote
1answer
439 views

SQLite3: Remove duplicates

Given the following table CREATE TABLE `sms` ( `_id` INTEGER, `thread_id` INTEGER, `address` TEXT, `person` INTEGER, `date` INTEGER, `protocol` INTEGER, `read` ...
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1answer
108 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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2answers
64 views

How to optimize a large join to create a WHERE IN

The following sqlite database query takes about 40 seconds on my Core i7. SELECT t.a FROM titles t WHERE t.a IN ( SELECT e.id FROM erpubtbl e JOIN abstract_mesh am ON am.pmid = e.pmid ...
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1answer
1k views

SQLite3 - remove duplicates by multiple columns

I'm looking for the most efficient way to remove duplicates from a table where id's are unique but there are equal rows when you check other columns. Example: id name age x 1 peter 25 ...
1
vote
1answer
3k 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
vote
1answer
24k views

How do I prevent SQLite database locks?

From SQLite FAQ I've known that: Multiple processes can have the same database open at the same time. Multiple processes can be doing a SELECT at the same time. But only one process can be ...
1
vote
1answer
69 views

Square root in SQLite studio

SQLite studio does not support square root function, so I have defined it in function editor as proc SqrtA {num} { set ans [expr {sqrt($num)}] return $ans } with function nameSqrtA and one input ...
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1answer
88 views

SQLite query rows nearest to hour

My question is similar to the one asked here. I'm new to SQL and I'm creating a weather app that stores part of the data locally in a db, so I'm writing the query using the sqlitedatabase java class ...
1
vote
1answer
42 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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1answer
95 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
152 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
3k 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
783 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 ...