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The following answer is based on the SQLite source code, mostly relying on the file parse.y (input for the lemon parser). TL;DR: The allowed series of characters for column and table names in CREATE TABLE statements are '-escaped strings of any kind (even keywords) Identifiers, which means ``` and "-escaped strings of any kind (even keywords)
The documentation for creating a table says that a table name can't begin with "sqlite_" but what other restrictions are there? Is there a formal definition anywhere of what is valid? SQLite seems surprisingly accepting as long as the name is quoted.
Note that numeric arguments in parentheses that following the type name (ex: "VARCHAR(255)") are ignored by SQLite - SQLite does not impose any length restrictions (other than the large global SQLITE_MAX_LENGTH limit) on the length of strings, BLOBs or numeric values.
Naming Conventions. Each database, table, column, index, trigger, or view has a name by which it is identified and almost always the name is supplied by the developer. The rules governing how a valid identifier is formed in SQLite are set out in the next few sections.
From SQLite documentation on CREATE TABLE, the only names forbidden are those that begin with sqlite_: Table names that begin with "sqlite_" are reserved for internal use. It is an error to attempt to create a table with a name that starts with "sqlite_".
As new keywords are added, legacy schemas that just happen to use those keywords as table or column names continue to work. However, the ability to use a keyword as an identifier sometimes leads to surprising outcomes.
The SQL standard specifies a large number of keywords which may not be used as the names of tables, indices, columns, databases, user-defined functions, collations, virtual table modules, or any other named object.
We should avoid redundant words or information in column names, mainly when such details can be inferred from the broader context of the table or the presence of other columns. For example, our e-commerce website has a table named Order , which contains information about each order.
You’ll apply these rules while naming anything inside the database – tables, columns, primary and foreign keys, stored procedures, functions, views, etc. Of course, you could decide to only set naming convention rules for tables and column names. That part is completely up to you.
1) You do not have to specify table names and/or column aliases in your queries all the time. 2) You can easily search your whole code for the column name. I think both arguments are flawed. The solution for both problems without using prefixes is easy. Here's my proposal:
One problem is caused by SQLite’s flexibility of column- and table names. A column named “SELECT”, “my column”, “this, that”, or even “this contains ‘single quotes'” is completely legal in SQLite. And what is legal is being used. So phpliteadmin needs to be able to handle these types of names as well, which is not really the case at the moment.
The maximum number of columns can be lowered at run-time using the sqlite3_limit(db,SQLITE_LIMIT_COLUMN,size) interface. Maximum Length Of An SQL Statement The maximum number of bytes in the text of an SQL statement is limited to SQLITE_MAX_SQL_LENGTH which defaults to 1,000,000,000.
This SQLite tutorial explains how to use SQLite ALIASES (temporary names for columns or tables) with syntax and examples. SQLite ALIASES can be used to create a temporary name for columns or tables.
ALTER TABLE RENAME COLUMN. The RENAME COLUMN TO syntax changes the column-name of table table-name into new-column-name. The column name is changed both within the table definition itself and also within all indexes, triggers, and views that reference the column.
Column Names. One of the most common types of expressions is the column name. The general format is fairly simple, consisting of just the column name. If there is any ambiguity between different tables, you can prefix the column name with an optional table name or a database and table name.
Syntax. create-table-stmt: CREATE TEMP TEMPORARY TABLE IF NOT EXISTS schema-name . table-name ( column-def table-constraint , ) table-options , AS select-stmt. column-def: show. select-stmt: show. table-constraint: show. table-options: show. 2. The CREATE TABLE command. The "CREATE TABLE" command is used to create a new table in an SQLite database.
Double quotes are used to quote identifiers like table and column names that would cause errors if not quoted. It's often easier when generating SQL statements to just automatically quote them instead of trying to figure out if they need to be or not.
A workaround is just to reset the column names with aliases: select f.mpg as mpg,f.cyl as cyl from vwmtcars f; mpg|cyl 21.0|6 22.8|4 21.4|6
column_name ENUM('small', 'medium', 'large') See MySQL Reference: The ENUM Type. To add to this, I find it's always better to restrict on the DB side AND on the app side. An Enum plus a Select box and you're covered.
To find the column name of the table, you should execute select * from tbl_name and you will get the result in sqlite3_stmt *. and check the column iterate over the total fetched column. Please refer following code for the same.