GIT | View Changed Details For Files By Commits | View List Of Files Changed During Different Commits

This below command will show changes made during last 3 commits for specific file defined

git diff HEAD~3..HEAD -- project/location/file.name

This command will list files changes made during last 3 commits

git diff --name-status HEAD~3..HEAD

This command will list files changes made during last 3 commits with changes

git diff HEAD~3..HEAD

Below command will show history of commits:

git log -3 git log -2

Below command will show difference between two commits:

git diff old_commit new_commit git diff 5300b....4ea31a 754e8d....c33 git diff --name-status 5300b....4ea31a 754e8d....c33

MySQL Table Create Index Remove Index List Index | Primary Indexing | Unique Indexing | Field Indexing | FullText Indexing

/* Primary INDEXING */
ALTER TABLE `TABLE_NAME` ADD PRIMARY KEY (`ID`);

/* General INDEXING (1 or more field) */
ALTER TABLE `TABLE_NAME` ADD INDEX `INDEX_NAME` (`FIELD_1`, `FIELD_2`);

/* Unique INDEXING (1 or more field) */
ALTER TABLE `TABLE_NAME` ADD UNIQUE `INDEX_NAME` (`FIELD_1`, `FIELD_2`);

/* Fulltext INDEXING (1 or more field) */
ALTER TABLE `TABLE_NAME` ADD FULLTEXT `INDEX_NAME` (`FIELD_1`, `FIELD_2`);

/* Remove INDEXING */
DROP INDEX `INDEX_NAME` ON `TABLE_NAME`;

/* List INDEXING */
SHOW INDEX FROM `TABLE_NAME`;

MYSQL : SQL For Create Table Example

CREATE TABLE `table_name` (
  `id` BIGINT(20) UNSIGNED NOT NULL AUTO_INCREMENT,
  `int_field` BIGINT(20) NOT NULL DEFAULT '0',
  `string_field` VARCHAR(255) NULL DEFAULT NULL COLLATE 'utf8_unicode_ci',
  `long_text_field` LONGTEXT NULL COLLATE 'utf8_unicode_ci',
  `time_stamp_field` TIMESTAMP NULL DEFAULT NULL,
  `date_field` DATE NULL DEFAULT NULL,
  `date_time_field` DATETIME NULL DEFAULT NULL,
  `tinyint_field` TINYINT(1) NOT NULL DEFAULT '0',
  `double_field` DOUBLE(30,10) NULL DEFAULT '0.0000000000',
  `enum_field` ENUM('TRUE','FALSE') NULL DEFAULT 'TRUE' COLLATE 'utf8_unicode_ci',
  `set_field` SET('XA','XB','XC') NULL DEFAULT 'XA,XB' COLLATE 'utf8_unicode_ci',
  `uuid` VARCHAR(70) NULL DEFAULT NULL COLLATE 'utf8_unicode_ci',
  PRIMARY KEY (`id`),
  UNIQUE INDEX `uuid` (`uuid`),
  INDEX `int_field_index` (`int_field`),
  INDEX `int_field_index_complex` (`int_field`, `string_field`)
) COLLATE='utf8_general_ci' ENGINE=InnoDB;

MYSQL Backup Database Using Command Line | MYSQL Import / Restore Database Using Command Line

To take backup database, you need to execute following command:

mysqldump -u root -p password db_name > /tmp/sql_file.sql


And you can import/restore database using following command:

mysql -u root -p password db_name < /tmp/sql_file.sql

Simple try & catch TagLib | Tag Library for Grails GSP views

First you have to create a TagLib as below:

With following contents:

package com.pkm.taglib

class TryCatchTagLib {
    static namespace = "ui"

    def Try = { attrs, body ->
        try {
            out << body()
            request.exception = null
        }
        catch (Throwable e) {
            request.exception = e
        }
    }

    def Catch = { attrs, body ->
        if (request.exception) {
            out << body(exception: request.exception)
            request.exception = null
        }
    }
}

And use of try-catch as below:

<ui:try>
    SOME WORK I AM TRYING
</ui:try>
<ui:catch>
    GOT EXCEPTION=${exception}
</ui:catch>

Grails Groovy Sample DataSource Configuration For Database Connection

You need to edit DataSource.groovy file as below:

dataSource {
    pooled = true
    jmxExport = true
    driverClassName = "com.mysql.jdbc.Driver"
    dialect = "org.hibernate.dialect.MySQL5InnoDBDialect"
    dbCreate = "update"
    username = "root"
    password = ""
    logSql = false
    loggingSql = false
    properties {
        maxActive = 1000
        maxIdle = 100
        minIdle = 50
        initialSize = 1
        minEvictableIdleTimeMillis = 60000
        timeBetweenEvictionRunsMillis = 60000
        numTestsPerEvictionRun = 3
        maxWait = 10000
        testOnBorrow = true
        testWhileIdle = true
        testOnReturn = true
        validationQuery = "SELECT 1"
        minEvictableIdleTimeMillis = 1800000
        timeBetweenEvictionRunsMillis = 1800000
    }
}
hibernate {
    cache.use_second_level_cache = true
    cache.use_query_cache = true
    cache.region.factory_class = 'net.sf.ehcache.hibernate.EhCacheRegionFactory'
    cache.provider_class = 'net.sf.ehcache.hibernate.EhCacheProvider'
    format_sql = false
    use_sql_comments = false
}

// environment specific settings
environments {
    development {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
            logSql = true
            loggingSql = true
        }
    }
    test {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
            logSql = true
            loggingSql = true
        }
    }
    production {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
        }
    }
}
log4j = {
    debug 'org.hibernate.SQL'
    trace 'org.hibernate.type.descriptor.sql.BasicBinder'
}

Grails Groovy Use Groovy Source Class As Singleton Bean | Custom Bean Definition | Transactional Bean

This will act as a transnational bean

First put the below settings to 'Config.groovy'

grails.hibernate.cache.queries = true
grails.databinding.convertEmptyStringsToNull = true

Need to add/modify below contents to 'BuildConfig.groovy' to enable database connection using MYSQL:

grails.project.dependency.resolver = "maven" // or ivy
grails.project.dependency.resolution = {
    // inherit Grails' default dependencies
    inherits("global") {
        // specify dependency exclusions here; for example, uncomment this to disable ehcache:
        // excludes 'ehcache'
    }
    log "error" // log level of Ivy resolver, either 'error', 'warn', 'info', 'debug' or 'verbose'
    checksums true // Whether to verify checksums on resolve
    legacyResolve false // whether to do a secondary resolve on plugin installation, not advised and here for backwards compatibility

    repositories {
        inherits true // Whether to inherit repository definitions from plugins

        grailsPlugins()
        grailsHome()
        mavenLocal()
        grailsCentral()
        mavenCentral()
        // uncomment these (or add new ones) to enable remote dependency resolution from public Maven repositories
        //mavenRepo "http://repository.codehaus.org"
        //mavenRepo "http://download.java.net/maven/2/"
        //mavenRepo "http://repository.jboss.com/maven2/"
        mavenRepo "https://oauth.googlecode.com/svn/code/maven"
    }

    dependencies {
        // specify dependencies here under either 'build', 'compile', 'runtime', 'test' or 'provided' scopes e.g.
        compile "org.springframework:spring-orm:$springVersion"
        runtime 'mysql:mysql-connector-java:5.1.29'
        runtime 'org.springframework:spring-test:4.0.5.RELEASE'
        runtime "commons-httpclient:commons-httpclient:3.1"
        runtime "org.apache.httpcomponents:httpclient:4.3.3"
        runtime 'net.oauth.core:oauth-httpclient4:20090913'
    }

    plugins {
        build ":tomcat:7.0.55"
        runtime ":hibernate4:4.3.6.1"
        compile ":rendering:1.0.0"
        compile ":browser-detection:0.4.3"
        compile ':cache:1.1.8'
        compile ":mail:1.0.5"
        compile ":asset-pipeline:1.9.9"
        compile ':quartz:1.0.2'
    }
}

Below may be you database configuration (DataSource.groovy):

dataSource {
    pooled = true
    jmxExport = true
    driverClassName = "com.mysql.jdbc.Driver"
    dialect = "org.hibernate.dialect.MySQL5InnoDBDialect"
    dbCreate = "update"
    username = "root"
    password = ""
    logSql = false
    loggingSql = false
    properties {
        maxActive = 1000
        maxIdle = 100
        minIdle = 50
        initialSize = 1
        minEvictableIdleTimeMillis = 60000
        timeBetweenEvictionRunsMillis = 60000
        numTestsPerEvictionRun = 3
        maxWait = 10000
        testOnBorrow = true
        testWhileIdle = true
        testOnReturn = true
        validationQuery = "SELECT 1"
        minEvictableIdleTimeMillis = 1800000
        timeBetweenEvictionRunsMillis = 1800000
    }
}
hibernate {
    cache.use_second_level_cache = true
    cache.use_query_cache = true
    cache.region.factory_class = 'net.sf.ehcache.hibernate.EhCacheRegionFactory'
    cache.provider_class = 'net.sf.ehcache.hibernate.EhCacheProvider'
    format_sql = false
    use_sql_comments = false
}

// environment specific settings
environments {
    development {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
            logSql = true
            loggingSql = true
        }
    }
    test {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
            logSql = true
            loggingSql = true
        }
    }
    production {
        dataSource {
            url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
        }
    }
}
log4j = {
    debug 'org.hibernate.SQL'
    trace 'org.hibernate.type.descriptor.sql.BasicBinder'
}

Now create a domain class like below:

package com.pritom

class Home {
    Long id
    String name
    String roll

    static constraints = {
        name blank: false
        roll blank: false, unique: true
    }
}

Below is the most important class which will be act as a singleton bean in our system:

package com.pritom

import org.springframework.transaction.annotation.Transactional
/**
 * Created by pritom on 21/11/2017.
 */
@Transactional(rollbackFor = [Exception, NoClassDefFoundError])
class MyBean {
    {
        println("BEAN-INITIALIZATION----------------$from------------------")
    }

    private String from = null

    void setFrom(String x) {
        this.from = x
    }

    void testPrint(String a) {
        println("Bean-class=${this.toString()}===${a}-----------$from")
        Thread.sleep(2000L)
        if (true) new Home(name: "Home-" + Home.count(), roll: String.valueOf(System.currentTimeMillis())).save()
        println("Home-count=${Home.count()}")
        if (true) throw new NoClassDefFoundError("Yeah!!!")
    }
}

We are not completed yet, need to initialize bean from resource.groovy as below:

beans = {
    myBean(MyBean) { bean ->
        bean.scope = 'singleton' // Set bean as singleton
        from = "Resource.groovy" // Set value to a field of class MyBean when initializing
    }
}

And finally test bean from some controller like below:

package com.pritom

class HomeController {
    def myBean

    def index() {
        try {
            myBean.testPrint("1")
            myBean.testPrint("2")
        }
        catch (Throwable ex) {
            println("Error=${ex.getMessage()}")
        }
        render ""
    }
}

And you can download source code from here