Java JDBC中，MySQL字段类型转换jdbcType
2020-08-28 本文已影响0人
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概述
MySQL里的数据字段类型与Java数据类型的对应标准。
1. 类型映射关系
MySQL类型类型、JDBC类型、Java类型的映射关系
| MySQL 数据类 型 | Java jdbcType | 默认返回的Java类型 |
|---|---|---|
| BIT(1) (new in MySQL-5.0) | BIT | java.lang.Boolean |
| TINYINT | TINYINT | java.lang.Boolean if the configuration property tinyInt1isBit is set to true (the default) and the storage size is 1, or java.lang.Integer if not. |
| BOOL, BOOLEAN | TINYINT | See TINYINT, above as these are aliases for TINYINT(1), currently. |
| SMALLINT[(M)] [UNSIGNED] | SMALLINT [UNSIGNED] | java.lang.Integer (regardless of whether it is UNSIGNED or not) |
| MEDIUMINT[(M)] [UNSIGNED] | MEDIUMINT [UNSIGNED] | java.lang.Integer (regardless of whether it is UNSIGNED or not) |
| INT,INTEGER[(M)] [UNSIGNED] | INTEGER [UNSIGNED] | java.lang.Integer, if UNSIGNED java.lang.Long |
| BIGINT[(M)] [UNSIGNED] | BIGINT [UNSIGNED] | java.lang.Long, if UNSIGNED java.math.BigInteger |
| FLOAT[(M,D)] | FLOAT | java.lang.Float |
| DOUBLE[(M,B)] | DOUBLE | java.lang.Double |
| DECIMAL[(M[,D])] | DECIMAL | java.math.BigDecimal |
| DATE | DATE | java.sql.Date |
| DATETIME | DATETIME | java.sql.Timestamp |
| TIMESTAMP[(M)] | TIMESTAMP | java.sql.Timestamp |
| TIME | TIME | java.sql.Time |
| YEAR[(2,4)] | YEAR | If yearIsDateType configuration property is set to false, then the returned object type is java.sql.Short. If set to true (the default), then the returned object is of type java.sql.Datewith the date set to January 1st, at midnight. |
| CHAR(M) | CHAR | java.lang.String (unless the character set for the column is BINARY, then byte[] is returned. |
| VARCHAR(M) [BINARY] | VARCHAR | java.lang.String (unless the character set for the column is BINARY, then byte[] is returned. |
| BINARY(M) | BINARY | byte[] |
| VARBINARY(M) | VARBINARY | byte[] |
| TINYBLOB | TINYBLOB | byte[] |
| TINYTEXT | VARCHAR | java.lang.String |
| BLOB | BLOB | byte[] |
| TEXT | VARCHAR | java.lang.String |
| MEDIUMBLOB | MEDIUMBLOB | byte[] |
| MEDIUMTEXT | VARCHAR | java.lang.String |
| LONGBLOB | LONGBLOB | byte[] |
| LONGTEXT | VARCHAR | java.lang.String |
| ENUM('value1','value2',...) | CHAR | java.lang.String |
| SET('value1','value2',...) | CHAR | java.lang.String |
2. 类型转换关系
允许的跨类型相互转换的对应关系
| MySQL数据类型 | 可转换为的Java类型 |
|---|---|
| CHAR, VARCHAR, BLOB, TEXT, ENUM, and SET | java.lang.String，java.io.InputStream，java.io.Reader，java.sql.Blob，java.sql.Clob |
| FLOAT, REAL, DOUBLE PRECISION, NUMERIC, DECIMAL, TINYINT, SMALLINT, MEDIUMINT, INTEGER, BIGINT | java.lang.String, java.lang.Short, java.lang.Integer, java.lang.Long, java.lang.Double, java.math.BigDecimal |
| DATE, TIME, DATETIME, TIMESTAMP | java.lang.String, java.sql.Date, java.sql.Timestamp |
