sqlite3提供了多个命令来查看数据库的schema

".tables"命令可以查看当前数据库所有的表

比如，示例14：

sqlite> .tables

tbl1

tbl2

sqlite>

".tables"和在list模式下执行下面的语句相似:

SELECT name FROM sqlite_master WHERE type IN ('table','view') AND name NOT LIKE 'sqlite_%' UNION ALL SELECT name FROM sqlite_temp_master WHERE type IN ('table','view') ORDER BY 1

实际上, 如果你查看sqlite3程序的源码(found in the source tree in the file src/shell.c)，you'll find exactly the above query.

另外，".tables"命令后也可以跟一参数，它是一个pattern，这样命令就只列出表名和该参数匹配的表。

比如，示例14-1：

sqlite> .tables

.tables

android_metadata bookmarks system

bluetooth_devices secure

sqlite> .tables s%

.tables s%

secure sqlite_sequence system

sqlite>

".indices"命令列出指定表的所有indices（索引）。第一个参数为表的名字。

比如，示例15：

sqlite> .schema system

.schema system

CREATE TABLE system (_id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT UNIQUE ON C

ONFLICT REPLACE,value TEXT);

CREATE INDEX systemIndex1 ON system (name);

sqlite> .tables

.tables

android_metadata bookmarks system

bluetooth_devices secure

sqlite> .indices system

.indices system

sqlite_autoindex_system_1

systemIndex1

sqlite>

".schema"命令，在没有参数的情况，它会显示最初用于创建数据库的CREATE TABLE和CREATE INDEX的SQL语句。比如，示例16

".schema"命令可以包含一个参数，它是一个pattern，用于对表进行过滤，这时只会显示满足条件的表和所有索引的SQL语句。

比如，示例15和示例17.

示例16：

sqlite> .schema

.schema

CREATE TABLE android_metadata (locale TEXT);

CREATE TABLE bluetooth_devices (_id INTEGER PRIMARY KEY,name TEXT,addr TEXT,chan

nel INTEGER,type INTEGER);

CREATE TABLE bookmarks (_id INTEGER PRIMARY KEY,title TEXT,folder TEXT,intent TE

XT,shortcut INTEGER,ordering INTEGER);

CREATE TABLE secure (_id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT UNIQUE ON C

ONFLICT REPLACE,value TEXT);

CREATE TABLE system (_id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT UNIQUE ON C

ONFLICT REPLACE,value TEXT);

CREATE INDEX bookmarksIndex1 ON bookmarks (folder);

CREATE INDEX bookmarksIndex2 ON bookmarks (shortcut);

CREATE INDEX secureIndex1 ON secure (name);

CREATE INDEX systemIndex1 ON system (name);

sqlite>

示例17：

sqlite> .schema s%

.schema s%

CREATE TABLE secure (_id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT UNIQUE ON C

ONFLICT REPLACE,value TEXT);

CREATE TABLE sqlite_sequence(name,seq);

CREATE TABLE system (_id INTEGER PRIMARY KEY AUTOINCREMENT,name TEXT UNIQUE ON C

ONFLICT REPLACE,value TEXT);

CREATE INDEX secureIndex1 ON secure (name);

CREATE INDEX systemIndex1 ON system (name);

sqlite>

".schema"命令功能和下面的语句相似:

SELECT sql FROM (SELECT * FROM sqlite_master UNION ALL SELECT * FROM sqlite_temp_master) WHERE type!='meta' ORDER BY tbl_name, type DESC, name

如果你传了一个参数给".schema"，以表明只想得到表的schema而包括索引的schema，那么SQL语句应该如下:

SELECT sql FROM (SELECT * FROM sqlite_master UNION ALL SELECT * FROM sqlite_temp_master) WHERE type!='meta' AND sql NOT NULL AND name NOT LIKE 'sqlite_%' ORDER BY substr(type,2,1), name

如果你想 “.schema”支持参数. 那么SQL语句应该如下:

SELECT sql FROM (SELECT * FROM sqlite_master UNION ALL SELECT * FROM sqlite_temp_master) WHERE tbl_name LIKE '%s' AND type!='meta' AND sql NOT NULL AND name NOT LIKE 'sqlite_%' ORDER BY substr(type,2,1), name

这里SQL语句中的"%s"将被你传入的参数代替. 你就可以只显示一部分的schema.

事实上".tables"的也是采用这种"LIKE"的方式，进行pattern查询的。

".databases"命令将列出当前connection中所有的数据库。

一般至少包含2个，一个是"main", the original database opened.另一个是"temp", the database used for temporary tables.