可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效,请关闭广告屏蔽插件后再试):
问题:
I am trying to find a way to extract information about my tables in SQL Server (2008).
The data I need needs to include the description of the table (filled from the Description property in the Properties Window), a list of fields of that table and their respective data types.
Is there any way I can extract such meta-data? I presume I have to use some sys
sp but I'n not sure which one.
回答1:
To get the description data, you unfortunately have to use sysobjects/syscolumns to get the ids:
SELECT u.name + '.' + t.name AS [table],
td.value AS [table_desc],
c.name AS [column],
cd.value AS [column_desc]
FROM sysobjects t
INNER JOIN sysusers u
ON u.uid = t.uid
LEFT OUTER JOIN sys.extended_properties td
ON td.major_id = t.id
AND td.minor_id = 0
AND td.name = 'MS_Description'
INNER JOIN syscolumns c
ON c.id = t.id
LEFT OUTER JOIN sys.extended_properties cd
ON cd.major_id = c.id
AND cd.minor_id = c.colid
AND cd.name = 'MS_Description'
WHERE t.type = 'u'
ORDER BY t.name, c.colorder
You can do it with info-schema, but you'd have to concatenate etc to call OBJECT_ID() - so what would be the point?
回答2:
Generic information about tables and columns can be found in these tables:
select * from INFORMATION_SCHEMA.TABLES
select * from INFORMATION_SCHEMA.COLUMNS
The table description is an extended property, you can query them from sys.extended_properties:
select
TableName = tbl.table_schema + '.' + tbl.table_name,
TableDescription = prop.value,
ColumnName = col.column_name,
ColumnDataType = col.data_type
FROM information_schema.tables tbl
INNER JOIN information_schema.columns col
ON col.table_name = tbl.table_name
AND col.table_schema = tbl.table_schema
LEFT JOIN sys.extended_properties prop
ON prop.major_id = object_id(tbl.table_schema + '.' + tbl.table_name)
AND prop.minor_id = 0
AND prop.name = 'MS_Description'
WHERE tbl.table_type = 'base table'
回答3:
You could try sp_help <Name of object>
回答4:
I liked @Andomar's answer best, but I needed the column descriptions also. Here is his query modified to include those also. (Uncomment the last part of the WHERE clause to return only rows where either description is non-null).
SELECT
TableName = tbl.table_schema + '.' + tbl.table_name,
TableDescription = tableProp.value,
ColumnName = col.column_name,
ColumnDataType = col.data_type,
ColumnDescription = colDesc.ColumnDescription
FROM information_schema.tables tbl
INNER JOIN information_schema.columns col
ON col.table_name = tbl.table_name
LEFT JOIN sys.extended_properties tableProp
ON tableProp.major_id = object_id(tbl.table_schema + '.' + tbl.table_name)
AND tableProp.minor_id = 0
AND tableProp.name = 'MS_Description'
LEFT JOIN (
SELECT sc.object_id, sc.column_id, sc.name, colProp.[value] AS ColumnDescription
FROM sys.columns sc
INNER JOIN sys.extended_properties colProp
ON colProp.major_id = sc.object_id
AND colProp.minor_id = sc.column_id
AND colProp.name = 'MS_Description'
) colDesc
ON colDesc.object_id = object_id(tbl.table_schema + '.' + tbl.table_name)
AND colDesc.name = col.COLUMN_NAME
WHERE tbl.table_type = 'base table'
--AND tableProp.[value] IS NOT NULL OR colDesc.ColumnDescription IS NOT null
回答5:
Using Object Catalog Views:
SELECT T.NAME AS [TABLE NAME], C.NAME AS [COLUMN NAME], P.NAME AS [DATA TYPE], P.MAX_LENGTH AS[SIZE], CAST(P.PRECISION AS VARCHAR) +‘/’+ CAST(P.SCALE AS VARCHAR) AS [PRECISION/SCALE]
FROM ADVENTUREWORKS.SYS.OBJECTS AS T
JOIN ADVENTUREWORKS.SYS.COLUMNS AS C
ON T.OBJECT_ID=C.OBJECT_ID
JOIN ADVENTUREWORKS.SYS.TYPES AS P
ON C.SYSTEM_TYPE_ID=P.SYSTEM_TYPE_ID
WHERE T.TYPE_DESC=‘USER_TABLE’;
Using Information Schema Views
SELECT TABLE_SCHEMA, TABLE_NAME, COLUMN_NAME, ORDINAL_POSITION,
COLUMN_DEFAULT, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH,
NUMERIC_PRECISION, NUMERIC_PRECISION_RADIX, NUMERIC_SCALE,
DATETIME_PRECISION
FROM ADVENTUREWORKS.INFORMATION_SCHEMA.COLUMNS
回答6:
If you are pulling your queries using java code, there is a great class that can be used, ResultSetMetaData, that can retrieve column names and the properties of the columns (type and length).
Example
ResultSet rs = null;
rs = sql.executeQuery();
if (rs != null) {
if (rs.next()) {
ResultSetMetaData rsmd = rs.getMetaData();
for (int i = 1; i <= rsmd.getColumnCount(); i++) {
System.out.println("column name: "
+ rsmd.getColumnName(i));
System.out.println("column size: "
+ rsmd.getColumnDisplaySize(i));
}
}
回答7:
Depending on how much metadata you want, this is working for me:
where could be the whole thing like Northwind.dbo.Products or just Products
SELECT c.name Field,
t.name Type,
c.Precision,
c.Scale,
c.is_nullable,
c.collation_name
FROM sys.columns c
INNER JOIN sys.types t ON t.system_type_id=c.system_type_id
WHERE object_id=object_id('<table to inspect>')
ORDER BY column_id
回答8:
Check this out:
SELECT TABLE_SCHEMA ,
TABLE_NAME ,
COLUMN_NAME ,
ORDINAL_POSITION ,
COLUMN_DEFAULT ,
DATA_TYPE ,
CHARACTER_MAXIMUM_LENGTH ,
NUMERIC_PRECISION ,
NUMERIC_PRECISION_RADIX ,
NUMERIC_SCALE ,
DATETIME_PRECISION
FROM INFORMATION_SCHEMA.COLUMNS
where TABLE_SCHEMA in ('dbo','meta')
and table_name in (select name from sys.tables)
order by TABLE_SCHEMA , TABLE_NAME ,ORDINAL_POSITION
回答9:
I use this SQL code to get all the information about a column.
SELECT
COL.COLUMN_NAME,
ORDINAL_POSITION,
DATA_TYPE,
CHARACTER_MAXIMUM_LENGTH,
NUMERIC_PRECISION,
NUMERIC_PRECISION_RADIX,
NUMERIC_SCALE,
DATETIME_PRECISION,
IS_NULLABLE,
CONSTRAINT_TYPE,
COLUMNPROPERTY(object_id(COL.TABLE_NAME), COL.COLUMN_NAME, 'IsIdentity') IS_IDENTITY,
COLUMNPROPERTY(object_id(COL.TABLE_NAME), COL.COLUMN_NAME, 'IsComputed') IS_COMPUTED
FROM INFORMATION_SCHEMA.COLUMNS COL
LEFT OUTER JOIN
(
SELECT COLUMN_NAME, CONSTRAINT_TYPE
FROM INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE A
INNER JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS B
ON A.CONSTRAINT_NAME = B.CONSTRAINT_NAME
WHERE A.TABLE_NAME = 'User'
) CONS
ON COL.COLUMN_NAME = CONS.COLUMN_NAME
WHERE COL.TABLE_NAME = 'User'
回答10:
Easiest way to get basic metadata summary is to use a temp table and then use EXEC function:
SELECT * INTO #TempTable FROM TableName
EXEC [tempdb].[dbo].[sp_help] N'#TempTable'
For all columns in the table, this will give you
Column Name,
Data Type,
Computed Length,
Prec,
Scale,
Nullable,
TrimTrailingBlanks,
FixedLenNullInSource,
Collation Type
回答11:
If you simply want to view the information in a convenient way, Red Gate's SQL Prompt might help.
If you hover over the object text in a query window SQL Prompt will display the MS_Description extended property text in a tooltip. Clicking on the tooltip will open a dialog displaying the column information and also the object's DDL.
http://www.red-gate.com/products/sql-development/sql-prompt/
回答12:
If it is OK to use .NET code I'd suggest using SMO: http://msdn.microsoft.com/en-us/library/ms162169.aspx, In your particular case it would be the Table class http://msdn.microsoft.com/en-us/library/microsoft.sqlserver.management.smo.table.aspx
This would be a more portable solution than using version specific system views and tables.
If this is something you are going to use on a regular basis - you might want to write a simple console application, perhaps with a runtime T4 code generator http://msdn.microsoft.com/en-us/library/ee844259.aspx
If it's just a one-off task - you could use my LiveDoco's( http://www.livedoco.com ) export to XML feature with an optional XSLT transform or I'm sure there are free tools out there that can do this.
This one looks okay: http://sqldbdoc.codeplex.com/ - supports XML via XSLT, but I'm not sure if you can run it for a selection of tables though (With LiveDoco you can).
回答13:
SELECT
sc.name AS ColumnName
,ep.*
FROM
sys.columns AS sc
INNER JOIN sys.extended_properties AS ep
ON ep.major_id = sc.[object_id]
AND ep.minor_id = sc.column_id
WHERE
--here put your desired table
sc.[object_id] = OBJECT_ID('[Northwind].[dbo].[Products]')
-- this is optional, remove this and you get all extended props
AND ep.name = 'MS_Description'
回答14:
select Col.name Columnname,prop.Value Description, tbl.name Tablename, sch.name schemaname
from sys.columns col left outer join sys.extended_properties prop
on prop.major_id = col.object_id and prop.minor_id = col.column_id
inner join sys.tables tbl on col.object_id = tbl.object_id
Left outer join sys.schemas sch on sch.schema_id = tbl.schema_id
回答15:
I just finished a .net library with a few useful queries that return strongly typed C# objects for code gen/ t4 templates.
nuget SqlMeta
Project Site
github source
/// <summary>
/// Get All Table Names
/// </summary>
/// <returns></returns>
public List<string> GetTableNames()
{
var sql = @"SELECT name
FROM dbo.sysobjects
WHERE xtype = 'U'
AND name <> 'sysdiagrams'
order by name asc";
return databaseWrapper.Call(connection => connection.Query<string>(
sql: sql))
.ToList();
}
/// <summary>
/// Get table info by schema and table or null for all
/// </summary>
/// <param name="schema"></param>
/// <param name="table"></param>
/// <returns></returns>
public List<SqlTableInfo> GetTableInfo(string schema = null, string table = null)
{
var result = new List<SqlTableInfo>();
var sql = @"SELECT
c.TABLE_CATALOG AS [TableCatalog]
, c.TABLE_SCHEMA AS [Schema]
, c.TABLE_NAME AS [TableName]
, c.COLUMN_NAME AS [ColumnName]
, c.ORDINAL_POSITION AS [OrdinalPosition]
, c.COLUMN_DEFAULT AS [ColumnDefault]
, c.IS_NULLABLE AS [Nullable]
, c.DATA_TYPE AS [DataType]
, c.CHARACTER_MAXIMUM_LENGTH AS [CharacterMaxLength]
, c.CHARACTER_OCTET_LENGTH AS [CharacterOctetLenth]
, c.NUMERIC_PRECISION AS [NumericPrecision]
, c.NUMERIC_PRECISION_RADIX AS [NumericPrecisionRadix]
, c.NUMERIC_SCALE AS [NumericScale]
, c.DATETIME_PRECISION AS [DatTimePrecision]
, c.CHARACTER_SET_CATALOG AS [CharacterSetCatalog]
, c.CHARACTER_SET_SCHEMA AS [CharacterSetSchema]
, c.CHARACTER_SET_NAME AS [CharacterSetName]
, c.COLLATION_CATALOG AS [CollationCatalog]
, c.COLLATION_SCHEMA AS [CollationSchema]
, c.COLLATION_NAME AS [CollationName]
, c.DOMAIN_CATALOG AS [DomainCatalog]
, c.DOMAIN_SCHEMA AS [DomainSchema]
, c.DOMAIN_NAME AS [DomainName]
, IsPrimaryKey = CONVERT(BIT, (SELECT
COUNT(*)
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS tc
, INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE cu
WHERE CONSTRAINT_TYPE = 'PRIMARY KEY'
AND tc.CONSTRAINT_NAME = cu.CONSTRAINT_NAME
AND tc.TABLE_NAME = c.TABLE_NAME
AND cu.TABLE_SCHEMA = c.TABLE_SCHEMA
AND cu.COLUMN_NAME = c.COLUMN_NAME)
)
, IsIdentity = CONVERT(BIT, (SELECT
COUNT(*)
FROM sys.objects obj
INNER JOIN sys.COLUMNS col
ON obj.object_id = col.object_id
WHERE obj.type = 'U'
AND obj.Name = c.TABLE_NAME
AND col.Name = c.COLUMN_NAME
AND col.is_identity = 1)
)
FROM INFORMATION_SCHEMA.COLUMNS c
WHERE (@Schema IS NULL
OR c.TABLE_SCHEMA = @Schema)
AND (@TableName IS NULL
OR c.TABLE_NAME = @TableName)
";
var columns = databaseWrapper.Call(connection => connection.Query<SqlColumnInfo>(
sql: sql,
param: new { Schema = schema, TableName = table },
commandType: CommandType.Text)
.ToList());
var refs = this.GetReferentialConstraints(table: table, schema: schema);
foreach (var tableName in columns.Select(info => info.TableName).Distinct())
{
var tableColumns = columns.Where(info => info.TableName == tableName).ToList();
var children = refs.Where(c => c.UniqueTableName == tableName).ToList();
var parents = refs.Where(c => c.TableName == tableName).ToList();
result.Add(new SqlTableInfo
{
TableName = tableName,
Columns = tableColumns,
ChildConstraints = children,
ParentConstraints = parents
});
}
return result;
}
public List<SqlReferentialConstraint> GetReferentialConstraints(string table = null, string schema = null)
{
//https://technet.microsoft.com/en-us/library/aa175805%28v=sql.80%29.aspx
//https://technet.microsoft.com/en-us/library/Aa175805.312ron1%28l=en-us,v=sql.80%29.jpg
//https://msdn.microsoft.com/en-us/library/ms186778.aspx
var sql = @"
SELECT
KCU1.CONSTRAINT_NAME AS [ConstraintName]
, KCU1.TABLE_NAME AS [TableName]
, KCU1.COLUMN_NAME AS [ColumnName]
, KCU2.CONSTRAINT_NAME AS [UniqueConstraintName]
, KCU2.TABLE_NAME AS [UniqueTableName]
, KCU2.COLUMN_NAME AS [UniqueColumnName]
, RC.MATCH_OPTION AS [MatchOption]
, RC.UPDATE_RULE AS [UpdateRule]
, RC.DELETE_RULE AS [DeleteRule]
FROM INFORMATION_SCHEMA.REFERENTIAL_CONSTRAINTS RC
LEFT JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU1 ON KCU1.CONSTRAINT_CATALOG = RC.CONSTRAINT_CATALOG
AND KCU1.CONSTRAINT_SCHEMA = RC.CONSTRAINT_SCHEMA
AND KCU1.CONSTRAINT_NAME = RC.CONSTRAINT_NAME
LEFT JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE KCU2 ON KCU2.CONSTRAINT_CATALOG = RC.UNIQUE_CONSTRAINT_CATALOG
AND KCU2.CONSTRAINT_SCHEMA = RC.UNIQUE_CONSTRAINT_SCHEMA
AND KCU2.CONSTRAINT_NAME = RC.UNIQUE_CONSTRAINT_NAME
WHERE KCU1.ORDINAL_POSITION = KCU2.ORDINAL_POSITION
AND (@Table IS NULL
OR KCU1.TABLE_NAME = @Table
OR KCU2.TABLE_NAME = @Table)
AND (@Schema IS NULL
OR KCU1.TABLE_SCHEMA = @Schema
OR KCU2.TABLE_SCHEMA = @Schema)
";
return databaseWrapper.Call(connection => connection.Query<SqlReferentialConstraint>(
sql: sql,
param: new { Table = table, Schema = schema },
commandType: CommandType.Text))
.ToList();
}
/// <summary>
/// Get Primary Key Column by schema and table name
/// </summary>
/// <param name="schema"></param>
/// <param name="tableName"></param>
/// <returns></returns>
public string GetPrimaryKeyColumnName(string schema, string tableName)
{
var sql = @"SELECT
B.COLUMN_NAME
FROM INFORMATION_SCHEMA.TABLE_CONSTRAINTS A
, INFORMATION_SCHEMA.CONSTRAINT_COLUMN_USAGE B
WHERE CONSTRAINT_TYPE = 'PRIMARY KEY'
AND A.CONSTRAINT_NAME = B.CONSTRAINT_NAME
AND A.TABLE_NAME = @TableName
AND A.TABLE_SCHEMA = @Schema";
return databaseWrapper.Call(connection => connection.Query<string>(
sql: sql,
param: new { TableName = tableName, Schema = schema },
commandType: CommandType.Text))
.SingleOrDefault();
}
/// <summary>
/// Get Identity Column by table name
/// </summary>
/// <param name="tableName"></param>
/// <returns></returns>
public string GetIdentityColumnName(string tableName)
{
var sql = @"SELECT
c.Name
FROM sys.objects o
INNER JOIN sys.columns c ON o.object_id = c.object_id
WHERE o.type = 'U'
AND c.is_identity = 1
AND o.Name = @TableName";
return databaseWrapper.Call(connection => connection.Query<string>(
sql: sql,
param: new { TableName = tableName },
commandType: CommandType.Text))
.SingleOrDefault();
}
/// <summary>
/// Get All Stored Procedures by schema
/// </summary>
/// <param name="schema"></param>
/// <param name="procName"></param>
/// <returns></returns>
public List<SqlStoredProcedureInfo> GetStoredProcedureInfo(string schema = null, string procName = null)
{
var result = new List<SqlStoredProcedureInfo>();
var sql = @"SELECT
SPECIFIC_NAME AS [Name]
, SPECIFIC_SCHEMA AS [Schema]
, Created AS [Created]
, LAST_ALTERED AS [LastAltered]
FROM INFORMATION_SCHEMA.ROUTINES
WHERE ROUTINE_TYPE = 'PROCEDURE'
AND (SPECIFIC_SCHEMA = @Schema
OR @Schema IS NULL)
AND (SPECIFIC_NAME = @ProcName
OR @ProcName IS NULL)
AND ((SPECIFIC_NAME NOT LIKE 'sp_%'
AND SPECIFIC_NAME NOT LIKE 'procUtils_GenerateClass'
AND (SPECIFIC_SCHEMA = @Schema
OR @Schema IS NULL))
OR SPECIFIC_SCHEMA <> @Schema)";
var sprocs = databaseWrapper.Call(connection => connection.Query<SqlStoredProcedureInfo>(
sql: sql,
param: new { Schema = schema, ProcName = procName },
commandType: CommandType.Text).ToList());
foreach (var s in sprocs)
{
s.Parameters = GetStoredProcedureInputParameters(sprocName: s.Name, schema: schema);
s.ResultColumns = GetColumnInfoFromStoredProcResult(storedProcName: s.Name, schema: schema);
result.Add(s);
}
return result;
}
/// <summary>
/// Get Column info from Stored procedure result set
/// </summary>
/// <param name="schema"></param>
/// <param name="storedProcName"></param>
/// <returns></returns>
public List<DataColumn> GetColumnInfoFromStoredProcResult(string schema, string storedProcName)
{
//this one actually needs to use the dataset because it has the only accurate information about columns and if they can be null or not.
var sb = new StringBuilder();
if (!String.IsNullOrEmpty(schema))
{
sb.Append(String.Format("exec [{0}].[{1}] ", schema, storedProcName));
}
else
{
sb.Append(String.Format("exec [{0}] ", storedProcName));
}
var prms = GetStoredProcedureInputParameters(schema, storedProcName);
var count = 1;
foreach (var param in prms)
{
sb.Append(String.Format("{0}=null", param.Name));
if (count < prms.Count)
{
sb.Append(", ");
}
count++;
}
var ds = new DataSet();
using (var sqlConnection = (SqlConnection)databaseWrapper.GetOpenDbConnection())
{
using (var sqlAdapter = new SqlDataAdapter(sb.ToString(), sqlConnection))
{
if (sqlConnection.State != ConnectionState.Open) sqlConnection.Open();
sqlAdapter.SelectCommand.ExecuteReader(CommandBehavior.SchemaOnly);
sqlConnection.Close();
sqlAdapter.FillSchema(ds, SchemaType.Source, "MyTable");
}
}
var list = new List<DataColumn>();
if (ds.Tables.Count > 0)
{
list = ds.Tables["MyTable"].Columns.Cast<DataColumn>().ToList();
}
return list;
}
/// <summary>
/// Get the input parameters for a stored procedure
/// </summary>
/// <param name="schema"></param>
/// <param name="sprocName"></param>
/// <returns></returns>
public List<SqlParameterInfo> GetStoredProcedureInputParameters(string schema = null, string sprocName = null)
{
var sql = @"SELECT
SCHEMA_NAME(schema_id) AS [Schema]
, P.Name AS Name
, @ProcName AS ProcedureName
, TYPE_NAME(P.user_type_id) AS [ParameterDataType]
, P.max_length AS [MaxLength]
, P.Precision AS [Precision]
, P.Scale AS Scale
, P.has_default_value AS HasDefaultValue
, P.default_value AS DefaultValue
, P.object_id AS ObjectId
, P.parameter_id AS ParameterId
, P.system_type_id AS SystemTypeId
, P.user_type_id AS UserTypeId
, P.is_output AS IsOutput
, P.is_cursor_ref AS IsCursor
, P.is_xml_document AS IsXmlDocument
, P.xml_collection_id AS XmlCollectionId
, P.is_readonly AS IsReadOnly
FROM sys.objects AS SO
INNER JOIN sys.parameters AS P ON SO.object_id = P.object_id
WHERE SO.object_id IN (SELECT
object_id
FROM sys.objects
WHERE type IN ('P', 'FN'))
AND (SO.Name = @ProcName
OR @ProcName IS NULL)
AND (SCHEMA_NAME(schema_id) = @Schema
OR @Schema IS NULL)
ORDER BY P.parameter_id ASC";
var result = databaseWrapper.Call(connection => connection.Query<SqlParameterInfo>(
sql: sql,
param: new { Schema = schema, ProcName = sprocName },
commandType: CommandType.Text))
.ToList();
return result;
}
Foreign Key Metadata