Basic mysql operations,

Basic mysql operations,

I. Basic operations

After connecting to Mysql, add a semicolon (;) to the end of an SQL statement.

• Create a database

# When creating data, you can add a back quotation mark (a key on the TAB key) before and after the database name so that you can create a database with a keyword. Otherwise, an error is returned.
Mysql> create database customer; Query OK, 1 row affected (0.00 sec)

• View mysql version

mysql> select version();+-----------+| version() |+-----------+| 5.6.38    |+-----------+1 row in set (0.00 sec)

• View Current Database

mysql> select database();+------------+| database() |+------------+| NULL       |+------------+1 row in set (0.00 sec)

• View the current logon Username

mysql> select user();+----------------+| user()         |+----------------+| root@localhost |+----------------+1 row in set (0.00 sec)

• View the current logon Username

mysql> select current_user();+----------------+| current_user() |+----------------+| root@localhost |+----------------+1 row in set (0.00 sec)

• View current date and time

mysql> select curtime(),curdate(),now();+-----------+------------+---------------------+| curtime() | curdate()  | now()               |+-----------+------------+---------------------+| 15:43:50  | 2018-01-15 | 2018-01-15 15:43:50 |+-----------+------------+---------------------+1 row in set (0.00 sec)

• View the number of databases

mysql> show databases;+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || test               |+--------------------+4 rows in set (0.01 sec)

• Deletes a specified database.

Drop database Name

• Switch a database to the current database

Use Database Name

mysql> use testDatabase changedmysql> select database();+------------+| database() |+------------+| test       |+------------+1 row in set (0.00 sec)

• View Character Set

mysql> show variables like 'char%';+--------------------------+--------------------------+| Variable_name            | Value                    |+--------------------------+--------------------------+| character_set_client     | gbk                      || character_set_connection | gbk                      || character_set_database   | latin1                   || character_set_filesystem | binary                   || character_set_results    | gbk                      || character_set_server     | latin1                   || character_set_system     | utf8                     || character_sets_dir       | c:\mysql\share\charsets\ |+--------------------------+--------------------------+8 rows in set (0.00 sec)

• Set the character set of the connection server and the current client

mysql> set names utf8;Query OK, 0 rows affected (0.00 sec)

• View the character sets supported by the current service

mysql> show charset;+----------+-----------------------------+---------------------+--------+| Charset  | Description                 | Default collation   | Maxlen |+----------+-----------------------------+---------------------+--------+| big5     | Big5 Traditional Chinese    | big5_chinese_ci     |      2 || dec8     | DEC West European           | dec8_swedish_ci     |      1 || cp850    | DOS West European           | cp850_general_ci    |      1 || hp8      | HP West European            | hp8_english_ci      |      1 || koi8r    | KOI8-R Relcom Russian       | koi8r_general_ci    |      1 || latin1   | cp1252 West European        | latin1_swedish_ci   |      1 || latin2   | ISO 8859-2 Central European | latin2_general_ci   |      1 || swe7     | 7bit Swedish                | swe7_swedish_ci     |      1 || ascii    | US ASCII                    | ascii_general_ci    |      1 || ujis     | EUC-JP Japanese             | ujis_japanese_ci    |      3 || sjis     | Shift-JIS Japanese          | sjis_japanese_ci    |      2 || hebrew   | ISO 8859-8 Hebrew           | hebrew_general_ci   |      1 || tis620   | TIS620 Thai                 | tis620_thai_ci      |      1 || euckr    | EUC-KR Korean               | euckr_korean_ci     |      2 || koi8u    | KOI8-U Ukrainian            | koi8u_general_ci    |      1 || gb2312   | GB2312 Simplified Chinese   | gb2312_chinese_ci   |      2 || greek    | ISO 8859-7 Greek            | greek_general_ci    |      1 || cp1250   | Windows Central European    | cp1250_general_ci   |      1 || gbk      | GBK Simplified Chinese      | gbk_chinese_ci      |      2 || latin5   | ISO 8859-9 Turkish          | latin5_turkish_ci   |      1 || armscii8 | ARMSCII-8 Armenian          | armscii8_general_ci |      1 || utf8     | UTF-8 Unicode               | utf8_general_ci     |      3 || ucs2     | UCS-2 Unicode               | ucs2_general_ci     |      2 || cp866    | DOS Russian                 | cp866_general_ci    |      1 || keybcs2  | DOS Kamenicky Czech-Slovak  | keybcs2_general_ci  |      1 || macce    | Mac Central European        | macce_general_ci    |      1 || macroman | Mac West European           | macroman_general_ci |      1 || cp852    | DOS Central European        | cp852_general_ci    |      1 || latin7   | ISO 8859-13 Baltic          | latin7_general_ci   |      1 || utf8mb4  | UTF-8 Unicode               | utf8mb4_general_ci  |      4 || cp1251   | Windows Cyrillic            | cp1251_general_ci   |      1 || utf16    | UTF-16 Unicode              | utf16_general_ci    |      4 || utf16le  | UTF-16LE Unicode            | utf16le_general_ci  |      4 || cp1256   | Windows Arabic              | cp1256_general_ci   |      1 || cp1257   | Windows Baltic              | cp1257_general_ci   |      1 || utf32    | UTF-32 Unicode              | utf32_general_ci    |      4 || binary   | Binary pseudo charset       | binary              |      1 || geostd8  | GEOSTD8 Georgian            | geostd8_general_ci  |      1 || cp932    | SJIS for Windows Japanese   | cp932_japanese_ci   |      2 || eucjpms  | UJIS for Windows Japanese   | eucjpms_japanese_ci |      3 |+----------+-----------------------------+---------------------+--------+40 rows in set (0.02 sec)

• View database engines

mysql> show engines;+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+| Engine             | Support | Comment                | Transactions | XA   | Savepoints |+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+| FEDERATED          | NO      | Federated MySQL storage engine                | NULL         | NULL | NULL       || MRG_MYISAM         | YES     | Collection of identical MyISAM tables                | NO           | NO   | NO         || MyISAM             | YES     | MyISAM storage engine                | NO           | NO   | NO         || BLACKHOLE          | YES     | /dev/null storage engine (anything you write to it disappears) | NO           | NO   | NO         || CSV                | YES     | CSV storage engine                | NO           | NO   | NO         || MEMORY             | YES     | Hash based, stored in memory, useful for temporary tables      | NO           | NO   | NO         || ARCHIVE            | YES     | Archive storage engine                | NO           | NO   | NO         || InnoDB             | DEFAULT | Supports transactions, row-level locking, and foreign keys     | YES          | YES  | YES        || PERFORMANCE_SCHEMA | YES     | Performance Schema                | NO           | NO   | NO         |+--------------------+---------+----------------------------------------------------------------+--------------+------+------------+9 rows in set (0.01 sec)

• Modify the character set of a Database

mysql> alter database `db` character set utf8;Query OK, 1 row affected (0.00 sec)