Duplicating a SQLite table, indexes, and data [duplicate] - sql

Question

Is there an easy way to copy an existing table structure to a new one?
(dont need the data, only the structure -> like id INTEGER, name varchar(20) ...)
Thx

Answer 1

You could use a command like this:
CREATE TABLE copied AS SELECT * FROM mytable WHERE 0
but due to SQLite's dynamic typing, most type information would be lost.
If you need just a table that behaves like the original, i.e., has the same number and names of columns, and can store the same values, this is enough.
If you really need the type information exactly like the original, you can read the original SQL CREATE TABLE statement from the sqlite_master table, like this:
SELECT sql FROM sqlite_master WHERE type='table' AND name='mytable'

Answer 2

SQLite cannot clone table with PK, defaults and indices.
Hacking by another tool is necessary.
In shell, replace the table name by sed.
sqlite3 dbfile '.schema oldtable' | sed '1s/oldtable/newtable/' | sqlite3 dbfile
And you can check new table.
sqlite3 dbfile '.schema newtable'
Primary key, defaults and indices will be reserved.
I hope this command can help you.

Answer 3

sqlite> .schema
CREATE TABLE [About](
[id],
[name],
[value]);
.schema command will give you structure of About-table how it could be made by programming SQLite interpreter by hand, typing in commands.
Paste in and execute, the CREATE block giving the table new name:
sqlite> CREATE TABLE [AboutToo](
[id],
[name],
[value]);
.tables command now will show you have two tables, old and new, "copied".
sqlite> .tables
About AboutToo
p.s. sqlite> is command prompt you get in console after launching SQLite.exe interpreter. To get it go to www.sqlite.org

Answer 4

Just for the record - This worked for me:
CREATE TABLE mytable (
contact_id INTEGER PRIMARY KEY,
first_name TEXT NOT NULL,
last_name TEXT NOT NULL,
email TEXT NOT NULL UNIQUE,
phone TEXT NOT NULL UNIQUE
);
-- Two variations
INSERT INTO mytable VALUES ( 1, "Donald", "Duck", "noone#nowhere.com", "1234");
INSERT INTO mytable ( contact_id,first_name,last_name,email,phone ) VALUES ( 2, "Daisy", "Duck", "daisy#nowhere.com", "45678");
.output copied.sql
-- Add new table name
.print CREATE TABLE copied (
-- Comment out first line from SQL
SELECT "-- " || sql FROM sqlite_master WHERE type='table';
.output
.read copied.sql
.schema
select * from copied;
Beware that this only works if schema is wrapped after CREATE TABLE mytable (.
Otherwise you'll need some string replacement using .system

Answer 5

Yes by using the SQLiteStudio you can use the last icon in the structure table called create similar table from any existing table.

Answer 6

I would prefer :
> sqlite3 <db_file>
sqlite3 > .output <output_file>
sqlite3 > .dump <table_name>
The line above generates the dump of table that includes DDL and DML statement.
Make changes in this file, i.e. find and replace the table name with new table name
Also, replace "CREATE TRIGGER " with "CREATE TRIGGER <NEWTABLE>_" , this will replace existing triggers with trigger names with a new table name on it. That will make it unique and will not cause conflicts with existing triggers. Once all schema changes are implemented, read it back into database using .read
sqlite3 > .read output_file
This can be scripted in shell file using shell commands like :
echo ".dump <table>" | sqlite3 <db_file> > <table_file>
sed -i.bak "s/\b<table_name>\b/<new_table_name>/g" <table_file>
sed -i.bak "s/\bCREATE TRIGGER \b/CREATE TRIGGER <new_table_name_>/g" <table_file>
echo ".read <table_file>" | sqlite3 <db_file>
rm <table_name>.bak
For example :
If you have table T and new table is TClone in db file D with file F to be created : then
echo ".dump T" | sqlite3 D.sqlite > F
sed -i.bak "s/\bT\b/TClone/g" F
sed -i.bak "s/\bCREATE TRIGGER \b/CREATE TRIGGER TClone_>/g" F
echo ".read F" | sqlite3 D.sqlite
rm T.bak
Finally, you can generalize this script by creating a parameterized version where you can pass source_table, destination_table , db_file as parameters that can be used to clone any table.
I tested this and it works.
Testing :
sqlite3 <database_file>
sqlite3 > select * from <new_table>;
should give you same results as original table. and
sqlite3 > .schema <new_table>
should have same schema as that of original table with a new name.