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How to create table in MySQL for beginners?

You can create a new table in the default database using command ‘ CREATE TABLE tableName ‘ and ‘ DROP TABLE tableName ‘. You can also apply condition ‘ IF EXISTS ‘ or ‘ IF NOT EXISTS ‘. To create a table, you need to define all its columns, by providing the columns’ name, type, and attributes.

Why can’t I create a table in MySQL?

MySQL: Can’t create table When starting Cascade CMS for the first time or after importing a new MySQL database, administrators may see an error message in the log file similar to the following: ERROR : *** Startup task: DatabaseIndexAndKeyManagerfailed to execute successfully: java.sql.SQLException: Can’t create table ‘.\cascade\#sql-1648_8.frm’ (errno:150) This means that the collation for the tables is incorrect.

Drop the database. Create the database and alter it to use the proper collation as mentioned in the section. Re-import the database dump from before the last startup was attempted. Start Cascade CMS.

: MySQL: Can’t create table

What is key in MySQL CREATE TABLE?

MySQL PRIMARY KEY Constraint

The PRIMARY KEY constraint uniquely identifies each record in a table.Primary keys must contain UNIQUE values, and cannot contain NULL values.A table can have only ONE primary key; and in the table, this primary key can consist of single or multiple columns (fields).

How to create student table in MySQL?

Creating Tables – To see the tables in your database do: mysql> show tables; To create a table for students in this class we can do: mysql> CREATE TABLE student (lastName VARCHAR(20), firstName VARCHAR(20), -> major VARCHAR(20), bDay DATE); The format for the DATE is YYYY-MM-DD. To see if the table has been correctly set up do: mysql> DESCRIBE student; To enter data into the table use the command: mysql> INSERT INTO student -> VALUES (‘Duck’, ‘Donald’, ‘Dance’, ‘1934-06-09’);

How to show tables in MySQL?

MySQL SHOW TABLES command example – To use the SHOW TABLES command, you need to log on to the MySQL server first.

On opening the MySQL Command Line Client, enter your password. Select the specific database. Run the SHOW TABLES command to see all the tables in the database that has been selected.

How to add data in MySQL?

MySQL INSERT – ignore errors when inserting data – In case you face errors or any unexpected behavior while executing the insertion of rows into the MySQL table, the statement execution is interrupted. Rows with valid and invalid values are not added to the table.

• For example, execute the following query: INSERT INTO Products01 VALUES (’01’, ‘iPhoneX’, ‘Apple’, 35000, 3); This statement returns the error because the record with this ID already exists.
• Now, modify the statement with IGNORE.
• It allows you to insert rows with valid values but overpass the rows with invalid values.

INSERT IGNORE INTO Products01 VALUES (’01’, ‘iPhoneX’, ‘Apple’, 35000, 3); As a result, the script was executed without errors. MySQL will notify you that rows were added to the table.

How to create a table in MySQL with time?

Getting UTC time value – To get the UTC time, you use UTC_TIME function as follows: SELECT CURRENT_TIME (), UTC_TIME(); Code language: SQL (Structured Query Language) ( sql ) In this tutorial, we have been covered a lot about MySQL TIME data type and some commonly used temporal functions for manipulating TIME values. Was this tutorial helpful?

How to create a table in MySQL and set primary key?

Primary Key Using ALTER TABLE Statement – This statement allows us to do the modification into the existing table. When the table does not have a primary key, this statement is used to add the primary key to the column of an existing table.

1. Syntax
2. Following are the syntax of the ALTER TABLE statement to create a primary key in MySQL:
3. ALTER TABLE table_name ADD PRIMARY KEY(column_list);
4. The following statement creates a table ” Persons ” that have no primary key column into the table definition.
5. mysql> CREATE TABLE Persons ( Person_ID int NOT NULL, Name varchar(45), Age int, City varchar(25) );
6. After creating a table, if we want to add a primary key to this table, we need to execute the ALTER TABLE statement as below:
7. mysql> ALTER TABLE Persons ADD PRIMARY KEY(Person_ID);
8. We can see the output where both statements executed successfully.

If the table needs to add the primary key into a table that already has data into the column, then it must be sure to the column does not contains duplicates or null values.

Is it okay to create a table in MySQL without database?

Table Partitioning – partition_options can be used to control partitioning of the table created with CREATE TABLE, Not all options shown in the syntax for partition_options at the beginning of this section are available for all partitioning types. Please see the listings for the following individual types for information specific to each type, and see Chapter 24, Partitioning, for more complete information about the workings of and uses for partitioning in MySQL, as well as additional examples of table creation and other statements relating to MySQL partitioning.

PARTITION BY If used, a partition_options clause begins with PARTITION BY, This clause contains the function that is used to determine the partition; the function returns an integer value ranging from 1 to num, where num is the number of partitions. (The maximum number of user-defined partitions which a table may contain is 1024; the number of subpartitions—discussed later in this section—is included in this maximum.) Note The expression ( expr ) used in a PARTITION BY clause cannot refer to any columns not in the table being created; such references are specifically not permitted and cause the statement to fail with an error. (Bug #29444) HASH( expr ) Hashes one or more columns to create a key for placing and locating rows. expr is an expression using one or more table columns. This can be any valid MySQL expression (including MySQL functions) that yields a single integer value. For example, these are both valid CREATE TABLE statements using PARTITION BY HASH : CREATE TABLE t1 (col1 INT, col2 CHAR(5)) PARTITION BY HASH(col1); CREATE TABLE t1 (col1 INT, col2 CHAR(5), col3 DATETIME) PARTITION BY HASH ( YEAR(col3) ); You may not use either VALUES LESS THAN or VALUES IN clauses with PARTITION BY HASH, PARTITION BY HASH uses the remainder of expr divided by the number of partitions (that is, the modulus). For examples and additional information, see Section 24.2.4, “HASH Partitioning”, The LINEAR keyword entails a somewhat different algorithm. In this case, the number of the partition in which a row is stored is calculated as the result of one or more logical AND operations. For discussion and examples of linear hashing, see Section 24.2.4.1, “LINEAR HASH Partitioning”, KEY( column_list ) This is similar to HASH, except that MySQL supplies the hashing function so as to guarantee an even data distribution. The column_list argument is simply a list of 1 or more table columns (maximum: 16). This example shows a simple table partitioned by key, with 4 partitions: CREATE TABLE tk (col1 INT, col2 CHAR(5), col3 DATE) PARTITION BY KEY(col3) PARTITIONS 4; For tables that are partitioned by key, you can employ linear partitioning by using the LINEAR keyword. This has the same effect as with tables that are partitioned by HASH, That is, the partition number is found using the & operator rather than the modulus (see Section 24.2.4.1, “LINEAR HASH Partitioning”, and Section 24.2.5, “KEY Partitioning”, for details). This example uses linear partitioning by key to distribute data between 5 partitions: CREATE TABLE tk (col1 INT, col2 CHAR(5), col3 DATE) PARTITION BY LINEAR KEY(col3) PARTITIONS 5; The ALGORITHM= option is supported with PARTITION BY KEY, ALGORITHM=1 causes the server to use the same key-hashing functions as MySQL 5.1; ALGORITHM=2 means that the server employs the key-hashing functions implemented and used by default for new KEY partitioned tables in MySQL 5.5 and later. (Partitioned tables created with the key-hashing functions employed in MySQL 5.5 and later cannot be used by a MySQL 5.1 server.) Not specifying the option has the same effect as using ALGORITHM=2, This option is intended for use chiefly when upgrading or downgrading KEY partitioned tables between MySQL 5.1 and later MySQL versions, or for creating tables partitioned by KEY or LINEAR KEY on a MySQL 5.5 or later server which can be used on a MySQL 5.1 server. For more information, see Section 13.1.9.1, “ALTER TABLE Partition Operations”, mysqldump writes this option encased in versioned comments. ALGORITHM=1 is shown when necessary in the output of SHOW CREATE TABLE using versioned comments in the same manner as mysqldump, ALGORITHM=2 is always omitted from SHOW CREATE TABLE output, even if this option was specified when creating the original table. You may not use either VALUES LESS THAN or VALUES IN clauses with PARTITION BY KEY, RANGE( expr ) In this case, expr shows a range of values using a set of VALUES LESS THAN operators. When using range partitioning, you must define at least one partition using VALUES LESS THAN, You cannot use VALUES IN with range partitioning. Note For tables partitioned by RANGE, VALUES LESS THAN must be used with either an integer literal value or an expression that evaluates to a single integer value. In MySQL 8.0, you can overcome this limitation in a table that is defined using PARTITION BY RANGE COLUMNS, as described later in this section. Suppose that you have a table that you wish to partition on a column containing year values, according to the following scheme.

Partition Number:	Years Range:
	1990 and earlier
1	1991 to 1994
2	1995 to 1998
3	1999 to 2002
4	2003 to 2005
5	2006 and later

A table implementing such a partitioning scheme can be realized by the CREATE TABLE statement shown here: CREATE TABLE t1 ( year_col INT, some_data INT ) PARTITION BY RANGE (year_col) ( PARTITION p0 VALUES LESS THAN (1991), PARTITION p1 VALUES LESS THAN (1995), PARTITION p2 VALUES LESS THAN (1999), PARTITION p3 VALUES LESS THAN (2002), PARTITION p4 VALUES LESS THAN (2006), PARTITION p5 VALUES LESS THAN MAXVALUE ); PARTITION, VALUES LESS THAN, statements work in a consecutive fashion. VALUES LESS THAN MAXVALUE works to specify ” leftover ” values that are greater than the maximum value otherwise specified. VALUES LESS THAN clauses work sequentially in a manner similar to that of the case portions of a switch, case block (as found in many programming languages such as C, Java, and PHP). That is, the clauses must be arranged in such a way that the upper limit specified in each successive VALUES LESS THAN is greater than that of the previous one, with the one referencing MAXVALUE coming last of all in the list. RANGE COLUMNS( column_list ) This variant on RANGE facilitates partition pruning for queries using range conditions on multiple columns (that is, having conditions such as WHERE a = 1 AND b < 10 or WHERE a = 1 AND b = 10 AND c < 10 ). It enables you to specify value ranges in multiple columns by using a list of columns in the COLUMNS clause and a set of column values in each PARTITION, VALUES LESS THAN ( value_list ) partition definition clause. (In the simplest case, this set consists of a single column.) The maximum number of columns that can be referenced in the column_list and value_list is 16. The column_list used in the COLUMNS clause may contain only names of columns; each column in the list must be one of the following MySQL data types: the integer types; the string types; and time or date column types. Columns using BLOB, TEXT, SET, ENUM, BIT, or spatial data types are not permitted; columns that use floating-point number types are also not permitted. You also may not use functions or arithmetic expressions in the COLUMNS clause. The VALUES LESS THAN clause used in a partition definition must specify a literal value for each column that appears in the COLUMNS() clause; that is, the list of values used for each VALUES LESS THAN clause must contain the same number of values as there are columns listed in the COLUMNS clause. An attempt to use more or fewer values in a VALUES LESS THAN clause than there are in the COLUMNS clause causes the statement to fail with the error Inconsistency in usage of column lists for partitioning., You cannot use NULL for any value appearing in VALUES LESS THAN, It is possible to use MAXVALUE more than once for a given column other than the first, as shown in this example: CREATE TABLE rc ( a INT NOT NULL, b INT NOT NULL ) PARTITION BY RANGE COLUMNS(a,b) ( PARTITION p0 VALUES LESS THAN (10,5), PARTITION p1 VALUES LESS THAN (20,10), PARTITION p2 VALUES LESS THAN (50,MAXVALUE), PARTITION p3 VALUES LESS THAN (65,MAXVALUE), PARTITION p4 VALUES LESS THAN (MAXVALUE,MAXVALUE) ); Each value used in a VALUES LESS THAN value list must match the type of the corresponding column exactly; no conversion is made. For example, you cannot use the string '1' for a value that matches a column that uses an integer type (you must use the numeral 1 instead), nor can you use the numeral 1 for a value that matches a column that uses a string type (in such a case, you must use a quoted string: '1' ). For more information, see Section 24.2.1, "RANGE Partitioning", and Section 24.4, "Partition Pruning", LIST( expr ) This is useful when assigning partitions based on a table column with a restricted set of possible values, such as a state or country code. In such a case, all rows pertaining to a certain state or country can be assigned to a single partition, or a partition can be reserved for a certain set of states or countries. It is similar to RANGE, except that only VALUES IN may be used to specify permissible values for each partition. VALUES IN is used with a list of values to be matched. For instance, you could create a partitioning scheme such as the following: CREATE TABLE client_firms ( id INT, name VARCHAR(35) ) PARTITION BY LIST (id) ( PARTITION r0 VALUES IN (1, 5, 9, 13, 17, 21), PARTITION r1 VALUES IN (2, 6, 10, 14, 18, 22), PARTITION r2 VALUES IN (3, 7, 11, 15, 19, 23), PARTITION r3 VALUES IN (4, 8, 12, 16, 20, 24) ); When using list partitioning, you must define at least one partition using VALUES IN, You cannot use VALUES LESS THAN with PARTITION BY LIST, Note For tables partitioned by LIST, the value list used with VALUES IN must consist of integer values only. In MySQL 8.0, you can overcome this limitation using partitioning by LIST COLUMNS, which is described later in this section. LIST COLUMNS( column_list ) This variant on LIST facilitates partition pruning for queries using comparison conditions on multiple columns (that is, having conditions such as WHERE a = 5 AND b = 5 or WHERE a = 1 AND b = 10 AND c = 5 ). It enables you to specify values in multiple columns by using a list of columns in the COLUMNS clause and a set of column values in each PARTITION, VALUES IN ( value_list ) partition definition clause. The rules governing regarding data types for the column list used in LIST COLUMNS( column_list ) and the value list used in VALUES IN( value_list ) are the same as those for the column list used in RANGE COLUMNS( column_list ) and the value list used in VALUES LESS THAN( value_list ), respectively, except that in the VALUES IN clause, MAXVALUE is not permitted, and you may use NULL, There is one important difference between the list of values used for VALUES IN with PARTITION BY LIST COLUMNS as opposed to when it is used with PARTITION BY LIST, When used with PARTITION BY LIST COLUMNS, each element in the VALUES IN clause must be a set of column values; the number of values in each set must be the same as the number of columns used in the COLUMNS clause, and the data types of these values must match those of the columns (and occur in the same order). In the simplest case, the set consists of a single column. The maximum number of columns that can be used in the column_list and in the elements making up the value_list is 16. The table defined by the following CREATE TABLE statement provides an example of a table using LIST COLUMNS partitioning: CREATE TABLE lc ( a INT NULL, b INT NULL ) PARTITION BY LIST COLUMNS(a,b) ( PARTITION p0 VALUES IN( (0,0), (NULL,NULL) ), PARTITION p1 VALUES IN( (0,1), (0,2), (0,3), (1,1), (1,2) ), PARTITION p2 VALUES IN( (1,0), (2,0), (2,1), (3,0), (3,1) ), PARTITION p3 VALUES IN( (1,3), (2,2), (2,3), (3,2), (3,3) ) ); PARTITIONS num The number of partitions may optionally be specified with a PARTITIONS num clause, where num is the number of partitions. If both this clause and any PARTITION clauses are used, num must be equal to the total number of any partitions that are declared using PARTITION clauses. Note Whether or not you use a PARTITIONS clause in creating a table that is partitioned by RANGE or LIST, you must still include at least one PARTITION VALUES clause in the table definition (see below). SUBPARTITION BY A partition may optionally be divided into a number of subpartitions. This can be indicated by using the optional SUBPARTITION BY clause. Subpartitioning may be done by HASH or KEY, Either of these may be LINEAR, These work in the same way as previously described for the equivalent partitioning types. (It is not possible to subpartition by LIST or RANGE,) The number of subpartitions can be indicated using the SUBPARTITIONS keyword followed by an integer value. Rigorous checking of the value used in PARTITIONS or SUBPARTITIONS clauses is applied and this value must adhere to the following rules:

The value must be a positive, nonzero integer. No leading zeros are permitted. The value must be an integer literal, and cannot not be an expression. For example, PARTITIONS 0.2E+01 is not permitted, even though 0.2E+01 evaluates to 2, (Bug #15890)

partition_definition Each partition may be individually defined using a partition_definition clause. The individual parts making up this clause are as follows:

PARTITION partition_name Specifies a logical name for the partition. VALUES For range partitioning, each partition must include a VALUES LESS THAN clause; for list partitioning, you must specify a VALUES IN clause for each partition. This is used to determine which rows are to be stored in this partition. See the discussions of partitioning types in Chapter 24, Partitioning, for syntax examples. ENGINE MySQL accepts a ENGINE option for both PARTITION and SUBPARTITION, Currently, the only way in which this option can be used is to set all partitions or all subpartitions to the same storage engine, and an attempt to set different storage engines for partitions or subpartitions in the same table raises the error ERROR 1469 (HY000): The mix of handlers in the partitions is not permitted in this version of MySQL, COMMENT An optional COMMENT clause may be used to specify a string that describes the partition. Example: COMMENT = ‘Data for the years previous to 1999’ The maximum length for a partition comment is 1024 characters. DATA DIRECTORY and INDEX DIRECTORY DATA DIRECTORY and INDEX DIRECTORY may be used to indicate the directory where, respectively, the data and indexes for this partition are to be stored. Both the data_dir and the index_dir must be absolute system path names. As of MySQL 8.0.21, the directory specified in a DATA DIRECTORY clause must be known to InnoDB, For more information, see Using the DATA DIRECTORY Clause, You must have the FILE privilege to use the DATA DIRECTORY or INDEX DIRECTORY partition option. Example: CREATE TABLE th (id INT, name VARCHAR(30), adate DATE) PARTITION BY LIST(YEAR(adate)) ( PARTITION p1999 VALUES IN (1995, 1999, 2003) DATA DIRECTORY = ‘/var/appdata/95/data’ INDEX DIRECTORY = ‘/var/appdata/95/idx’, PARTITION p2000 VALUES IN (1996, 2000, 2004) DATA DIRECTORY = ‘/var/appdata/96/data’ INDEX DIRECTORY = ‘/var/appdata/96/idx’, PARTITION p2001 VALUES IN (1997, 2001, 2005) DATA DIRECTORY = ‘/var/appdata/97/data’ INDEX DIRECTORY = ‘/var/appdata/97/idx’, PARTITION p2002 VALUES IN (1998, 2002, 2006) DATA DIRECTORY = ‘/var/appdata/98/data’ INDEX DIRECTORY = ‘/var/appdata/98/idx’ ); DATA DIRECTORY and INDEX DIRECTORY behave in the same way as in the CREATE TABLE statement’s table_option clause as used for MyISAM tables. One data directory and one index directory may be specified per partition. If left unspecified, the data and indexes are stored by default in the table’s database directory. The DATA DIRECTORY and INDEX DIRECTORY options are ignored for creating partitioned tables if NO_DIR_IN_CREATE is in effect. MAX_ROWS and MIN_ROWS May be used to specify, respectively, the maximum and minimum number of rows to be stored in the partition. The values for max_number_of_rows and min_number_of_rows must be positive integers. As with the table-level options with the same names, these act only as ” suggestions ” to the server and are not hard limits. TABLESPACE May be used to designate an InnoDB file-per-table tablespace for the partition by specifying TABLESPACE `innodb_file_per_table`, All partitions must belong to the same storage engine. Placing InnoDB table partitions in shared InnoDB tablespaces is not supported. Shared tablespaces include the InnoDB system tablespace and general tablespaces.

subpartition_definition The partition definition may optionally contain one or more subpartition_definition clauses. Each of these consists at a minimum of the SUBPARTITION name, where name is an identifier for the subpartition. Except for the replacement of the PARTITION keyword with SUBPARTITION, the syntax for a subpartition definition is identical to that for a partition definition. Subpartitioning must be done by HASH or KEY, and can be done only on RANGE or LIST partitions. See Section 24.2.6, “Subpartitioning”,

Partitioning by Generated Columns Partitioning by generated columns is permitted. For example: CREATE TABLE t1 ( s1 INT, s2 INT AS (EXP(s1)) STORED ) PARTITION BY LIST (s2) ( PARTITION p1 VALUES IN (1) ); Partitioning sees a generated column as a regular column, which enables workarounds for limitations on functions that are not permitted for partitioning (see Section 24.6.3, “Partitioning Limitations Relating to Functions” ).

Can we CREATE TABLE inside table in MySQL?

There is no concept of nested table in mysql. But you can archive same things by settings relationships of parent child tables. I mean using primary key and foreign key. create : tblContinent Id (PK) Name create : tblCountry ID (PK) CID (foreign Key to tableContinent) Name So, this way you will have list of all continent and the country in each continent. H. Mahida H. Mahida 2,356 1 gold badge 13 silver badges 23 bronze badges 0 just an example to the @Mahida’s sol: 1. Parent table Automobile Child tables 1. Car 2. Truck 3. Bus Here Auto ID column is a Primary key to Automobile table and foreign to Car,Truck,Bus tables. Hope you got what you need. answered May 18, 2015 at 7:54 Vaibs Vaibs 2,028 22 silver badges 29 bronze badges

How to create table in MySQL for beginners?

You can create a new table in the default database using command ‘ CREATE TABLE tableName ‘ and ‘ DROP TABLE tableName ‘. You can also apply condition ‘ IF EXISTS ‘ or ‘ IF NOT EXISTS ‘. To create a table, you need to define all its columns, by providing the columns’ name, type, and attributes.