字符串转成整数

使用示例

import com.youngdatafan.sqlbuilder.enums.DatabaseType;
import com.youngdatafan.sqlbuilder.enums.FunctionType;
import com.youngdatafan.sqlbuilder.model.Function;
import com.youngdatafan.sqlbuilder.model.Model;
import com.youngdatafan.sqlbuilder.model.Query;
import com.youngdatafan.sqlbuilder.model.Schema;
import com.youngdatafan.sqlbuilder.model.Table;

public class Test {

    @org.junit.Test
    public void getFunction() {
        Schema schema = Schema.getSchema("");
        Table test = Table.getOriginalTable(schema, "test", "t");
        Query query = new Query();
        Model num = test.addField("num");
        Function function = Function.getFunction(FunctionType.TO_INT, num);
        query.addColumn("val", function);
        query.addFrom(test);
        System.out.println("oracle：");
        System.out.println(query.getDatabaseSql(DatabaseType.ORACLE));
        System.out.println();

        System.out.println("pg：");
        System.out.println(query.getDatabaseSql(DatabaseType.POSTGRESQL));
        System.out.println();

        System.out.println("clickhouse：");
        System.out.println(query.getDatabaseSql(DatabaseType.CLICKHOUSE));
        System.out.println();

        System.out.println("mysql：");
        System.out.println(query.getDatabaseSql(DatabaseType.MYSQL));
        System.out.println();

        System.out.println("sqlserver：");
        System.out.println(query.getDatabaseSql(DatabaseType.MSSQL));
        System.out.println();

        System.out.println("kdw：");
        System.out.println(query.getDatabaseSql(DatabaseType.KDW));
        System.out.println();
    }
}

根据数据源获取对于数据库的sql。

ORACLE

SELECT TRUNC(t."num",0) AS "val" FROM "test" t   

MYSQL

SELECT CONVERT(t.`num`, UNSIGNED INTEGER) AS `val` FROM `test` t  

POSTGRESQL

SELECT toDecimal64(t.num, 0) AS val FROM test t 

CLICKHOUSE

SELECT ROUND(t.num, 2) AS val FROM test t    

KDW

SELECT TRUNC(t.num,0) AS val FROM test t 

SQLSERVER

SELECT CAST(t.num AS int) AS val FROM test t