From 3454863ddba455c6e748d760290e9d65b45fdbb0 Mon Sep 17 00:00:00 2001 From: Chris Moos Date: Sat, 15 Nov 2014 20:19:45 -0700 Subject: [PATCH] Add support for returning table alias on Columns(). Currently the driver discards the column alias and the original table name. This change adds a new configuration parameter to include the table alias with the column name. This is useful because when mapping columns to structs, it is impossible to distinguish between duplicate column names when doing JOIN queries. --- AUTHORS | 1 + README.md | 15 +++++++++++++++ connection.go | 1 + packets.go | 17 +++++++++++++---- rows.go | 11 +++++++++-- utils.go | 7 +++++++ utils_test.go | 25 +++++++++++++------------ 7 files changed, 59 insertions(+), 18 deletions(-) diff --git a/AUTHORS b/AUTHORS index f0b070246..3a9e90620 100644 --- a/AUTHORS +++ b/AUTHORS @@ -14,6 +14,7 @@ Aaron Hopkins Arne Hormann Carlos Nieto +Chris Moos DisposaBoy Frederick Mayle Gustavo Kristic diff --git a/README.md b/README.md index 6a2b61e0e..a42d3eb39 100644 --- a/README.md +++ b/README.md @@ -166,6 +166,21 @@ Default: false `clientFoundRows=true` causes an UPDATE to return the number of matching rows instead of the number of rows changed. +##### `columnsWithAlias` + +``` +Type: bool +Valid Values: true, false +Default: false +``` + +When `columnsWithAlias` is true, calls to `sql.Rows.Columns()` will return the table alias and the column name separated by a dot. For example: + +``` +SELECT u.id FROM users as u +``` + +will return `u.id` instead of just `id` if `columnsWithAlias=true`. ##### `loc` diff --git a/connection.go b/connection.go index 67d3dbee8..264735632 100644 --- a/connection.go +++ b/connection.go @@ -45,6 +45,7 @@ type config struct { allowAllFiles bool allowOldPasswords bool clientFoundRows bool + columnsWithAlias bool } // Handles parameters set in DSN after the connection is established diff --git a/packets.go b/packets.go index f2e385bf8..255301e81 100644 --- a/packets.go +++ b/packets.go @@ -530,11 +530,20 @@ func (mc *mysqlConn) readColumns(count int) ([]mysqlField, error) { pos += n // Table [len coded string] - n, err = skipLengthEncodedString(data[pos:]) - if err != nil { - return nil, err + if mc.cfg.columnsWithAlias { + tableName, _, n, err := readLengthEncodedString(data[pos:]) + if err != nil { + return nil, err + } + pos += n + columns[i].tableName = string(tableName) + } else { + n, err = skipLengthEncodedString(data[pos:]) + if err != nil { + return nil, err + } + pos += n } - pos += n // Original table [len coded string] n, err = skipLengthEncodedString(data[pos:]) diff --git a/rows.go b/rows.go index 5ecaa9493..bb161c8d8 100644 --- a/rows.go +++ b/rows.go @@ -14,6 +14,7 @@ import ( ) type mysqlField struct { + tableName string name string flags fieldFlag fieldType byte @@ -37,8 +38,14 @@ type emptyRows struct{} func (rows *mysqlRows) Columns() []string { columns := make([]string, len(rows.columns)) - for i := range columns { - columns[i] = rows.columns[i].name + if rows.mc.cfg.columnsWithAlias { + for i := range columns { + columns[i] = rows.columns[i].tableName + "." + rows.columns[i].name + } + } else { + for i := range columns { + columns[i] = rows.columns[i].name + } } return columns } diff --git a/utils.go b/utils.go index 56f1b082e..c88e28c7d 100644 --- a/utils.go +++ b/utils.go @@ -215,6 +215,13 @@ func parseDSNParams(cfg *config, params string) (err error) { } cfg.collation = collation break + + case "columnsWithAlias": + var isBool bool + cfg.columnsWithAlias, isBool = readBool(value) + if !isBool { + return fmt.Errorf("Invalid Bool value: %s", value) + } // Time Location case "loc": diff --git a/utils_test.go b/utils_test.go index 6e50b09b9..bed58c1e4 100644 --- a/utils_test.go +++ b/utils_test.go @@ -21,18 +21,19 @@ var testDSNs = []struct { out string loc *time.Location }{ - {"username:password@protocol(address)/dbname?param=value", "&{user:username passwd:password net:protocol addr:address dbname:dbname params:map[param:value] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"user@unix(/path/to/socket)/dbname?charset=utf8", "&{user:user passwd: net:unix addr:/path/to/socket dbname:dbname params:map[charset:utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"user:password@tcp(localhost:5555)/dbname?charset=utf8&tls=true", "&{user:user passwd:password net:tcp addr:localhost:5555 dbname:dbname params:map[charset:utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"user:password@tcp(localhost:5555)/dbname?charset=utf8mb4,utf8&tls=skip-verify", "&{user:user passwd:password net:tcp addr:localhost:5555 dbname:dbname params:map[charset:utf8mb4,utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"user:password@/dbname?loc=UTC&timeout=30s&allowAllFiles=1&clientFoundRows=true&allowOldPasswords=TRUE&collation=utf8mb4_unicode_ci", "&{user:user passwd:password net:tcp addr:127.0.0.1:3306 dbname:dbname params:map[] loc:%p tls: timeout:30000000000 collation:224 allowAllFiles:true allowOldPasswords:true clientFoundRows:true}", time.UTC}, - {"user:p@ss(word)@tcp([de:ad:be:ef::ca:fe]:80)/dbname?loc=Local", "&{user:user passwd:p@ss(word) net:tcp addr:[de:ad:be:ef::ca:fe]:80 dbname:dbname params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.Local}, - {"/dbname", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname:dbname params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"@/", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"/", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"user:p@/ssword@/", "&{user:user passwd:p@/ssword net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, - {"unix/?arg=%2Fsome%2Fpath.ext", "&{user: passwd: net:unix addr:/tmp/mysql.sock dbname: params:map[arg:/some/path.ext] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false}", time.UTC}, + {"username:password@protocol(address)/dbname?param=value", "&{user:username passwd:password net:protocol addr:address dbname:dbname params:map[param:value] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"username:password@protocol(address)/dbname?param=value&columnsWithAlias=true", "&{user:username passwd:password net:protocol addr:address dbname:dbname params:map[param:value] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:true}", time.UTC}, + {"user@unix(/path/to/socket)/dbname?charset=utf8", "&{user:user passwd: net:unix addr:/path/to/socket dbname:dbname params:map[charset:utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"user:password@tcp(localhost:5555)/dbname?charset=utf8&tls=true", "&{user:user passwd:password net:tcp addr:localhost:5555 dbname:dbname params:map[charset:utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"user:password@tcp(localhost:5555)/dbname?charset=utf8mb4,utf8&tls=skip-verify", "&{user:user passwd:password net:tcp addr:localhost:5555 dbname:dbname params:map[charset:utf8mb4,utf8] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"user:password@/dbname?loc=UTC&timeout=30s&allowAllFiles=1&clientFoundRows=true&allowOldPasswords=TRUE&collation=utf8mb4_unicode_ci", "&{user:user passwd:password net:tcp addr:127.0.0.1:3306 dbname:dbname params:map[] loc:%p tls: timeout:30000000000 collation:224 allowAllFiles:true allowOldPasswords:true clientFoundRows:true columnsWithAlias:false}", time.UTC}, + {"user:p@ss(word)@tcp([de:ad:be:ef::ca:fe]:80)/dbname?loc=Local", "&{user:user passwd:p@ss(word) net:tcp addr:[de:ad:be:ef::ca:fe]:80 dbname:dbname params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.Local}, + {"/dbname", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname:dbname params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"@/", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"/", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"", "&{user: passwd: net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"user:p@/ssword@/", "&{user:user passwd:p@/ssword net:tcp addr:127.0.0.1:3306 dbname: params:map[] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, + {"unix/?arg=%2Fsome%2Fpath.ext", "&{user: passwd: net:unix addr:/tmp/mysql.sock dbname: params:map[arg:/some/path.ext] loc:%p tls: timeout:0 collation:33 allowAllFiles:false allowOldPasswords:false clientFoundRows:false columnsWithAlias:false}", time.UTC}, } func TestDSNParser(t *testing.T) {