The following statement creates a table named countries which has country_id column as the primary key. ) Code language: SQL (Structured Query Language) ( sql ) Creating SQLite primary key examples It is faster than using a primary key which is not an alias of the rowid.Īnother important note is that if you declare a column with the INTEGER type and PRIMARY KEY DESC clause, this column will not become an alias for the rowid column: CREATE TABLE table( Notice that if you assign another integer type such as BIGINT and UNSIGNED INT to the primary key column, this column will not be an alias for the rowid column.īecause the rowid table organizes its data as a B-tree, querying and sorting data of a rowid table are very fast. If a table has the primary key that consists of one column, and that column is defined as INTEGER then this primary key column becomes an alias for the rowid column. Tables that have rowid columns are called rowid tables. The rowid column is a key that uniquely identifies the rows in the table. When you create a table without specifying the WITHOUT ROWID option, SQLite adds an implicit column called rowid that stores 64-bit signed integer. However, to make the current version of SQLite compatible with the earlier version, SQLite allows the primary key column to contain NULL values. It means that the primary key column has an implicit NOT NULL constraint. In SQL standard, the primary key column must not contain NULL values. ) Code language: SQL (Structured Query Language) ( sql ) Second, in case primary key consists of two or more columns, you use the PRIMARY KEY table constraint to define the primary as shown in the following statement. SQLite allows you to define primary key in two ways:įirst, if the primary key has only one column, you use the PRIMARY KEY column constraint to define the primary key as follows: CREATE TABLE table_name( Each table has one and only one primary key. Introduction to SQLite primary keyĪ primary key is a column or group of columns used to identify the uniqueness of rows in a table. In this tutorial, you have learned various ways to export data in the SQLite database to a CSV file.Summary: in this tutorial, you will learn how to use SQLite PRIMARY KEY constraint to define a primary key for a table. Then, choose a single table to export the data.Īfter that, (1) choose the CSV as the export format, (2) specify the CSV file name, (3) check the column names in the first row, (4) choose comma (,) as the column separator, (5) treat the NULL value as empty string, (6) click Finish button to complete exporting.įinally, check the customer.csv file, you will see the following content: Next, choose the database and table that you want to export data check the Export table data. The following steps show you how to export data from a table to a CSV file.įirst, click the Tools > Export menu item The SQLiteStudio provides the export function that allows you to export data in a table or the result of a query to a CSV file. >sqlite3 -header -csv c:/sqlite/chinook.db data.csv Export SQLite database to a CSV file using SQliteStudio If you have a file named query.sql that contains the script to query data, you can execute the statements in the file and export data to a CSV file. >sqlite3 -header -csv c:/sqlite/chinook.db " select * from tracks " > tracks.csv Code language: SQL (Structured Query Language) ( sql ) If you check the data.csv file, you will see the following output.īesides using the dot-commands, you can use the options of the sqlite3 tool to export data from the SQLite database to a CSV file.įor example, the following command exports the data from the tracks table to a CSV file named tracks.csv. The following commands select data from the customers table and export it to the data.csv file. Issue the query to select data from the table to which you want to export.Set the output mode to CSV to instruct the sqlite3 tool to issue the result in the CSV mode.Turn on the header of the result set using the.To export data from the SQLite database to a CSV file, you use these steps: By using the sqlite3 tool, you can use the SQL statements and dot-commands to interact with the SQLite database. SQLite project provides you with a command-line program called sqlite3 or sqlite3.exe on Windows. Export SQLite Database to a CSV file using sqlite3 tool There are several ways to dump data from an SQLite database to a CSV file. Summary: in this tutorial, you will learn how to export SQLite database to a CSV file.
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