我正在尝试找到一种方法来提取有关我在 SQL Server (2008) 中的表的信息。
我需要的数据需要包括表的描述（从属性窗口中的描述属性填充）、该表的字段列表及其各自的数据类型。
有什么方法可以提取这些元数据？我想我必须使用一些 sys sp 但我不确定是哪一个。
【问题讨论】：
标签： sql sql-server metadata
有两种简单的方法：
选项 1
sp_help 'schema.table_name'
选项 2
SELECT * FROM INFORMATION_SCHEMA.columns c WHERE c.table_name = 'table_name'
【讨论】：
获取基本元数据摘要的最简单方法是使用临时表，然后使用 EXEC 函数：
SELECT * INTO #TempTable FROM TableName
EXEC [tempdb].[dbo].[sp_help] N'#TempTable'
对于表中的所有列，这将为您提供
列名,
数据类型,
计算长度,
前言，
规模，
可空，
修剪尾随空白，
固定LenNullInSource，
排序规则类型
【讨论】：
看看这个：
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
【讨论】：
有关表和列的一般信息可以在这些表中找到：
select * from INFORMATION_SCHEMA.TABLES
select * from INFORMATION_SCHEMA.COLUMNS
表描述是扩展属性，可以从sys.extended_properties查询：
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'
【讨论】：
INNER JOIN information_schema.columns col ON col.table_name = tbl.table_name AND col.TABLE_SCHEMA = tbl.TABLE_SCHEMA order by col.TABLE_NAME
我刚刚完成了一个 .net 库，其中包含一些有用的查询，这些查询返回代码 gen/t4 模板的强类型 C# 对象。
/// <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;
}
【讨论】：
我最喜欢@Andomar 的回答，但我也需要列说明。这是他的查询修改为也包括这些查询。 （取消注释 WHERE 子句的最后一部分以仅返回其中任一描述为非空的行）。
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
【讨论】：
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
【讨论】：
根据您需要多少元数据，这对我有用： 哪里可能是 Northwind.dbo.Products 之类的全部内容或只是 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
【讨论】：
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'
【讨论】：
我使用此 SQL 代码获取有关列的所有信息。
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'
【讨论】：
如果您使用 java 代码提取查询，可以使用一个很棒的类 ResultSetMetaData，它可以检索列名和列的属性（类型和长度）。
示例
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));
}
}
【讨论】：
如果可以使用 .NET 代码，我建议使用 SMO：http://msdn.microsoft.com/en-us/library/ms162169.aspx，在您的特定情况下，它将是 Table 类 http://msdn.microsoft.com/en-us/library/microsoft.sqlserver.management.smo.table.aspx 与使用特定于版本的系统视图和表格相比，这将是一种更便携的解决方案。
如果这是您要定期使用的东西 - 您可能想编写一个简单的控制台应用程序，也许使用运行时 T4 代码生成器http://msdn.microsoft.com/en-us/library/ee844259.aspx
如果这只是一项一次性任务 - 您可以使用我的 LiveDoco (http://www.livedoco.com) 导出到 XML 功能和可选的 XSLT 转换，或者我确信有免费工具可以做到这一点。 这个看起来不错：http://sqldbdoc.codeplex.com/ - 通过 XSLT 支持 XML，但我不确定您是否可以为选择的表运行它（使用 LiveDoco 可以）。
【讨论】：
如果您只是想以方便的方式查看信息，Red Gate 的 SQL Prompt 可能会有所帮助。
如果您将鼠标悬停在查询窗口中的对象文本上，SQL Prompt 将在工具提示中显示 MS_Description 扩展属性文本。单击工具提示将打开一个对话框，显示列信息以及对象的 DDL。
http://www.red-gate.com/products/sql-development/sql-prompt/
【讨论】：
使用对象目录视图：
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’;
使用信息架构视图
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
【讨论】：
你可以试试sp_help <Name of object>
【讨论】：
要获取描述数据，很遗憾您必须使用 sysobjects/syscolumns 来获取 id：
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
您可以使用 info-schema 来做到这一点，但您必须连接 etc 才能调用 OBJECT_ID() - 那有什么意义呢？
【讨论】：